Second Term Jss 2 Mathematics
NAME:…………………………………………
CLASS:…………………..
SECOND TERM: E– LEARNING NOTES
JS 2 (BASIC 8)
SUBJECT: MATHEMATICS
SCHEME OF WORK
WEEK TOPIC
- Revision of First Term Work.
- Simple Equations: Harder problems on Algebraic Fractions.
- Word Problems on algebraic Fractions. World problem leading to Simple Algebraic Fractions.
- Linear inequality in one variable. Graphical representations of solutions of linear inequalities in one variable.
- Graphs: plotting points on the Cartesian plane (the axis and plotting of points). Linear Equation in two variables – plotting the graph of Linear Equations in two variables
- More work on plotting and joining points to form plane shapes on Cartesian Planes.
- Graphs: Linear graphs from real life situations – plotting linear graphs from real life situation. Quantitative reasoning – solving quantitative aptitude problems.
- Plane Figures/shapes: Revision on properties of parallelogram rhombus and kite.
- Scale drawing – Drawing to scale to represent given distances. Solving problems on quantitative aptitude related to plane shapes/ figures
- Revision
- Examination.
WEEK 1
Topic: Revision of last term’s work using past examinations questions papers.
NOTE: Teachers should ensure all topics that seem complex are thoroughly explained for better understanding. Evaluation should be given and marked.
WEEK 2
TOPIC: SIMPLE EQUATION AND WORLD PROBLEMS
DEFINITION OF EQUATIONS
Equations are open sentences which have the equal sign. Solving an equation means finding a value of the unknown which makes the equation true. Any letter a, f, c, x etc. can be used as unknown. The set of values which make an equation true is called the truth set.
Example 1
Solve the following simple equations:
- 3a-8 = 10
- 10x – 7 = 27
- 4 + 5y = 19
Solution
- 3a – 8 = 10
Method 1
3a – 8 + 8 =10 +8
3a = 18
= 6
Method 2
3a – 8 = 10
3a = 10 + 8
3a = 18
a = = 6
Note: If a number is moved from one side to an equation over the equal sign to the other side, the sign of the number changes.
- 10x – 7 = 27
Method 1
10x – 7 + 7 = 27 + 7
10x = 34
x = 3.4
Method 2
10x – 7 = 27
10x = 27+ 7
x = = 3.4
EXAMPLE 2
Solve the following equations:
- 4(3y-2) = 6
- 2 (x-8) = 3(x+5)
Solution
- 4 (3y-2) = 6
Removing the bracket we have
12y-8=6
Solving the equation
12y= 6 +8 =14
y= =
- 2(x-8) = 3(x+5)
Removing the brackets
2x-16 = 3x+15
Collecting the like terms together and solving
-16-15 = 3x-2x
-31 = x
Or
x = -31
EXAMPLE 3
Solve the following equations
Solution
Multiply both sides by 3
a-2 = 12
a =12+2
a = 14
Multiply both sides by 7
5
35 + 3 = 2x
38 =2x
x =19
Collecting the like terms together
(L.C.M of 3 and x is 3x)
2 = 13x
WORD PROBLEM ON SIMPLE EQUATIONS
This is the same as solving simple equations.
EXAMPLE:
- I think of a number, add 3 to it and then divide the result by 5. If the answer equals the original number, what is the number?
- The average cost of a number of erasers is 50k. if all the erasers cost N 20, find the total number of erasers.
Solution:
- Let the number be x.
3 added to the number becomes: x+3
Divide the result by 5:
And since the result equals original number, we have,
Solving, we have,
x +3 = 5x
3 = 5x-x
3 = 4x
= x
- Let the number of erasers be y
Average cost of erasers = N
Average cost of erasers =
50 =
50y =
50y = 2000
y = 40 erasers
:
Solve the following equations;
READING ASSIGNMENT:
New General Mathematics for Junior Secondary Schools 2 by M. F. Macrae et al
WEEKEND ASSIGNMENT:
- Solve
- A sportswoman has a body of mass of xkg. Her mass is i4kg less than that of her friend. If their total mass is 76kg. Find the mass of each of them.
- A girl has 12 sweets. She eats n out of them. Find how many sweets she has left if n=2
WEEK 3
TOPIC: WORD PROBLEMS ON ALGEBRAIC FRACTIONS
CONTENT:
- Word problems leading to simple algebraic fractions
- Problem solving
WORD PROBLEMS LEADING TO SIMPLE ALGEBRAIC FRACTIONS
When solving word problems, the following points are important:
- Use a letter to represent the unknown
- Translate problem from words to algebraic form
- Make an equation out of it
- Solve equation completely to get the unknown
- Where it involve fraction, first clear the fraction using LCM
- Give the answer in a written form
- Check the result against the information given in the question
PROBLEM SOLVING
- Ojo add 15 to a number and then divide the sum by three. The result is twice the first number. Find the number.
Solution:
Let the number be
Ojo add 15 to
Ojo divide the result by 3:
The result is
This implies that:
Multiply both sides 3 to clear the fraction
Collecting like terms,
Dividing both side by 5, the result is 3 ie
Therefore, the number is 3
- I add 60 to a certain number and then divide the result by 12, the quotient is 6. Find the original number.
Solution:
Let the number be
I add 60 to the number i.e
Dividing result by 12 implies
Quotient means answer
Multiply through by 12 to clear the fraction: x12
This implies:
The original number is 12.
- Juliet is old and her brother is half of her age. The sum of their ages is half of their father’s age who is now 60. How old is Juliet and her brother?
Solution:
Juliet age is
Her brother’s age is half of hers i.e
Their Father’s age is 60 years and half of 60 is 30.
Sum of their ages is half of their father:
Multiply through by 2 to clear the fraction:
This means that: Juliet is 10 years and her brother is 5 years.
Evaluation:
- Find a number such that when 20 is added to ¼ of it, the result is times the original number.
- One-fifth of an even number added tone-sixth of the next even number makes a total of 15. Find the two numbers. (Hint: let the numbers be and ).
Reading Assignment:
New General Mathematics JSS-2 UBE Edition. Page 114 to 117.
WEEKEND ASSIGNMENT:
New General Mathematics JSS-2 UBE Edition. Ex. 13h: Attempt Q1 to Q16 Page 117 to 118.
[mediator_tech]
WEEK 4
TOPIC: LINEAR INEQUALITIES
CONTENT:
- Inequalities
- Graphs of inequalities
- Solution of inequalities
INEQUALITIES
In mathematics, we use the equal s sign, = , to show that quantities are the same. How ever, very often, quantities are different, or unequal. The inequalities symbols are as follows:
unequal to
less than
Take a and b to be any number points on number line below:
If a = +3 and b = +3
a b
-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7
a and b have the same position on the number line.
Hence, a = b
But if a = 1
and b = -4
then a b
or b a
b a
-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6
A linear inequality is an open sentence with an inequality sign.
For example: x + 2 7
Example:
The radius of a circle is less than 5m. What can be said about?
- Its circumference?
- Its area?
Solution
r 5m
- Circumference = 2r
Circumference 10m
Area 25m2
EVALUATION:
- State whether each of the following is true or false.
- 12 5 (c) -5 7
- 0-4 -3 (d) -2 -4
- Eraser cost 7 kobo each, x kobo is not enough to buy an eraser but a boy with y kobo is able to buy an eraser. Write down 3 different inequalities in terms of a or b or both.
Graphs of Inequalities in one Variable
Examples
- The inequality x 2 means that x can have any value less than 2. We can show these values on the number line below:
-2 -1 0 1 2 3
The heavy arrowed line on the number line illustrated above shows the range of values that x can have. The empty circle shows that the value 2 is not included; x can have any other value to the left of 2.
- The inequality means that x can have the value -1 or any value greater than -1. From the illustration below, the shaded circle shows that the value -1 is included.
-3 -2 -1 0 1 2
Evaluation:
Sketch the graphs of the following inequalities:
- X 4 c. X -3
- X d. X 5
SOLUTION OF INEQUALITIES
Example1:
Solve the inequality x + 4 6
Solution
x + 4 6
Subtract 4 from both sides.
X + 4-4 6 – 4
X 2
Example 2:
Solve 19 4 – 5x
Solution:
19 4 – 5x
Subtract 4 from both sides
19-4 4-4 -5x
15 -5x
Divide both sides by -5 and reverse the inequality sign.
-3 x
If -3 x, then x -3.
READING ASSIGNMENT:
NEW GENERAL MATHEMATICS FOR JSS 2 (UBE EDITION)
PG. 209 – 213.
WEEKEND ASSIGNMENT:
Ex. 22f 1-5; 22g 1-5; 22h 1-5
JSS 2 SECOND TERM MATHEMATICS LESSON NOTE
WEEK 5
TOPIC: GRAPH
Content:
- Plotting points on Cartesian plane
- Linear equation in two variables
- Graph of linear equation in two variables
PLOTTING POINTS ON CARTESIAN PLANE
Graph is a picture of numerical data. A familiar example is the representation of numbers on the number line. The positions of the number on the line are called points.
CARTESIAN PLANE
This is plane surface with axes drawn on it. The Cartesian is derived from a French philosopher and mathematician who work out the possibility of presenting geometry in a numerical form. His full name is Rene Descartes, hence the name Cartesian (+)y-axis
Vertical line Point of intersection (origin)
(-) (0, 0) (+) x-axis
Horizontal line
(-)
We describe a point on a Cartesian plane by two numbers say () called coordinates. is the distance of the point from vertical line called -axis and is the distance of the point from horizontal line called -axis. The figure illustrates more.
+3
+2 .A
B+1
-4 -3 -2 -1 +1 +2 +3 +4 +5
-1
.C -2 .D
-3
The position of each point is given by an ordered pair of number. These are called co-ordinates of the point. The first number is called the – coordinate and second number is called -coordinate. The coordinates are separated by a comma.
A(3,2) B(-2,1) C(-3,-2) D(3,-2)
Evaluation:
Plot the following points on a graph:
- (2,4), (5,1), (3,4),(1,1)
- (6,6), (1,6), (4,4), (1,4)
LINEAR GRAPH
This is also called straight line graph. A linear graph is obtained by plotting the points whose coordinates () satisfying a linear equation of the form where and are given constants and
gradient and
PLOTTING OF GRAPH
This is the process by which those recorded pairs of points in the in the table of values are now transferred onto the graph paper appropriately.
To do this accurately the following points are considered:
- Prepare a table of value for function or equation given
- Draw the axes (x-axis and y-axis)
- Choose the appropriate scale if not given
- Choose any convenient range of your choice for x if not given.
- Plot the points according to the calculated coordinate pairs
- Join the plotted points using rule for a straight line graph and curve for quadratic graph
Example:
Plot the graph of the function using values of from -3 to 2
Solution:
Note: Teacher should demonstrate the plotting of this graph in the class and extend examples to two distinct line graphs on this plane using single table of value.
EVALUATION:
Draw the graphs of the following functions:
- b. c.
READING ASSIGNMENT:
New General Mathematics JSS-2 UBE Edition page102-104.
WEEKEND ASSIGNMENT:
New General Mathematics JSS-2 UBE Edition page102, Ex. 12a Q1 to Q4
WEEK 6
TOPIC: PLANE SHAPES ON CARTESIAN PLANE
Content:
- Plotting and joining of points to form plane shapes
PLOTTING AND JOINING OF POINTS TO FORM PLANE SHAPES
Examples:
- Plot the points: P (-5, 3) Q (3, 5) R (-4,-4)
- Join the plotted points
- Name the shape obtained
Solution:
Q(3,5)
P(-4,3) 5
3
-4
R(4,-4) -4
Note: Teacher should give more examples in the class while course teaching this topic.
EVALUATION:
Using a graph paper, draw axes OX and OY and label the x-axis -7 to 7 and y-axis from -5 to 5. Using the same scale for each axis, plot the following points and join them together in the given order.
- A(2,5) B(-5,-2) C(4,4)
- P(-5,2) Q(0,5) R(7,2) S(0,0)
- Name each in questions (1) and (2) above
READING ASSIGNMENT:
New General Mathematics JSS-2 UBE Edition page104-109
WEEKEND ASSIGNMENT:
New General Mathematics JSS-2 UBE Edition page108, Ex. 12d Q1 to Q6
WEEK 7
TOPIC: GRAPHS
CONTENT:
- linear graphs from real life situation
- Quantitative reasoning on linear graph
LINEAR GRAPHS FROM REAL LIFE SITUATION
Example
A student walks along a road at a speed of 120m per minute.
- Make a table of values showing how far the students have walked after 0, 1, 2, 3, 4, 5 minutes.
- Using a scale of 1cm to 1min on the horizontal axis and 1cm to 100cm on the vertical axis, draw a graph of this information.
- Use the graph to find the following:
- How far the student has walked after 2.6min
- How long it takes the student to walk 500m.
Solution:
- Table of values is illustrated below:
Time (s) 0 1 2 3 4 5 6 Speed (km/h) 0 15 20 45 60 75 90 b.
600 x
500 x
Distance (m)
400
x
300
x
200
x
100
0 1 2 3 4 5
Time (min)
(c) i. 2.6 min corresponds to 310m (approximately). The student has walked about 310m after 2.6min.
ii. 500m corresponding to 4.2min (approximate). The student takes about 4.2min to walk 500m.
EVALUATION:
A girl walks along a road at a speed of 100m per minute.
- Copy and complete the table below:
Time (min) 0 1 2 3 4 5 6 Distance (m) 0 100 200
- Using a scale of 2cm to 1min on the horizontal axis and 2cm to 100m on the vertical axis, draw a graph of the information.
- Use your graph to find i. how far the girl has walked after 5.7 min, ii. how long it takes her to walk 335m
READING ASSIGNMENT:
New General Mathematics JSS 2 (UBE Edition), pg 119- 136
WEEKEND ASSIGNMENT:
New General Mathematics JSS 2 (UBE Edition), pg 119- 136
Ex. 14a. Q5; 14b.Q 2; 14c. Q1 page 121-125
[mediator_tech]
WEEK 8
TOPIC: PLANE FIGURES/SHAPES
CONTENT:
Properties of Quadrilateral (i.e. parallelogram, rhombus, and kite)
QUADRILATERAL
Any four sided plane figure is called a quadrilateral.
Examples of quadrilaterals are:
- PARALLELOGRAM
A parallelogram is a quadrilateral whose pairs are equal and parallel.
PROPERTIES OF PARALLELOGRAM
- Its opposite sides are parallel and equal
- Its opposite angles are equal
- Its diagonals bisect each other
- Each diagonal bisects the parallelogram into two congruent triangles
- The (4) angles together add up to 3600
Consider the parallelogram below:
A 10cm B
E
4cm
4cm
4cm
D 10cm C
Line AB =Line DC = 10cm
Line AB is parallel to line DC
Line AD = Line BC = 4cm
Line AD is parallel to line BC
Angle BAD = Angle BCD
Angle ADC = Angle ABC
Diagonal AC divides the parallelogram ABCD into two congruent triangles ABC and ADC
Diagonal DB divides the parallelogram ABCD into two congruent triangles DAB and DCB
The diagonals bisect each other at point E i.e.
AE = EC = and DE = EB
- RHOMBUS
A rhombus is a quadrilateral which has four sides equal length.
PROPERTIES OF RHOMBUS
- All four sides are equal in length.
- The opposite angles are equal.
- The diagonals are the lines of symmetry.
- The diagonals bisect each other at right angles.
A B
P
D C
Line AB = line BC = line DC = line AD, i.e.
AB = BC= DC = AD
AD is parallel to BC
AB is parallel to DC
<DAB = <BCD, and <DPC = <APD
<APB = <BPC = <DPC = <APD = 900
PA = PC and PB = PD
- KITE
A kite is a quadrilateral in which one diagonal is a line of symmetry.
Lines of symmetry
NOTE: Teachers should display these shapes using various class activities
EVALUATION / ACTIVITIES:
Draw a parallelogram on a cardboard paper such that its diagonals meet C. then cut out the parallelogram along the diagonals. What do you notice?
READING ASSIGNMENT:
New General Mathematics for JSS 2 (UBE Edition) , pg 32-38
WEEKEND ASSIGNMENT
New General Mathematics for JSS 2 (UBE Edition) , pg 37
Ex. 3d Q1-Q10
WEEK 9
TOPIC: SCALE DRAWING
Content:
- Scale
- Scale drawing
- Reading scale drawing Scale
SCALE
A scale simply means the dimension or proportion of objects in comparison to its original or actual size after the drawing. It is widely use in sciences especially in Geography, Biology, Mathematics, Physics, etc.
The scale of a drawing is determined by comparing the length of the drawing with the actual length of the object.
Scale
A is original
B is drawing
Diameter of A = 25cm Diameter of B = 10cm
Scale = the scale is 2 to 5, i.e 2 : 5 meaning 2cm represents 5cm
EVALUATION:
Use measurement to find the scale of the following shapes/figures:
Original
Drawing
Original
b.
Drawing
SCALE DRAWING
In scale drawing the materials needed are pencil, ruler and set square. The drawings should be on plane sheets or white papers. The dimensions of the actual object should be written on the drawing and a title has to accompany it. However, a rough sketch must be drawn first.
Example:
A measurement of 8000m is drawn to a scale where 1cm represents 500m. Find its length on the drawing.
Solution:
500m is represented by 1cm.
1m is represented by
8000m is represented by
Length on drawing = 16cm.
READING SCALE DRAWING
Reading scale drawing is common to map reading and interpretation. For instance, scales on maps are often given in the ratio form as 1 : .
A map of scale 1 : 50 000 means 1cm represents 50 000cm.
This means 1cm on map represents 50 000cm on land.
Map scale
Rearranging the above formula we have:
Actual distance = map scale x distance on map
OR Distance on map
Example:
Change the scale 1 : 800 000 to the form 1cm represents ….km.
Solution:
1:800 000 means 1cm represents 800 000cm.
But 1km = 100 000cm
1cm represents 800 000 100 000 = 8km
The scale is 1cm represents 8km.
EVALUATION
- Two cities are 70km apart. The distance between them is 20cm on the map. What is the scale of the map?
- Rewrite the following scales in the form 1:n
- 1cm represent 20 000cm
- 1cm represents 500 000cm
READING ASSIGNMENT:
New General Mathematics JSS 2, UBE Edition, pg 149 – 157
WEEKEND ASSIGNMENT:
New General Mathematics JSS 2, UBE Edition, pg 153
Ex. 1-3
WEEK 10: Revision
WEEK 11: Examination
END OF SECOND TERM WORK