2. SUB -TOPIC: SOLVING SIMPLE EQUATIONS
TOPIC: ALGEBRA
SUB -TOPIC: SOLVING SIMPLE EQUATIONS

3. Core competences to be achieved
Critical thinking and problem solving
Efficacy
learning to learn
Digital literacy

4. Solving simple equations
Activity: Solving simple equations by balancing method
Work in groups
Procedure
Look at the following objects:
Pictures of:
Masses of various objects
Standard masses
Beam balance

5. Cont.. Can you name objects provided? Have you seen them anywhere?
Where did you see them?
Put two similar standard masses on two sides of the beam balance . what do you notice? 
Put two different standard masses on two sides of the beam balance . what do you notice?

6. Cont….
g). Put 200 g mass on side A of the beam balance . put 100 g masses on side B of the beam balance. How many 100 g masses balance with 200 g mass?
h). Using the results from (g) , find the value of A if
100 + A = 200

7. Cont…
Try to balance various objects and standard masses on a beam balance. Which different masses balance each other? Record your results in the table below:
Standard mass
Two 100 g
Balances
One 200 g

8. Cont… Discussion: X + 50 = 100 is called a simple equation.
x is called an unknown
To find the value of x is to solve the equation
X +50
100 = A B

9. Cont.. To maintain balance:
What is added on side a must be added to side B
What is taken away side A must be taken away from side B

10. Example
Solve the equation x + 4 = 15

11. solution
Proceed as…..
X +4 15 =

12. Example cont….
Here, what is taken away from side A must be taken away from side B to maintain balance
So take away 4 from both sides
(x + 4) – 4 = 15 – 4
X = 11

13. Digital literacy application
Visit the website: and watch a simulation on solving equations by balancing method. From the simulation answer the following questions:
What mass should be added to 150 g mass to make it 350 g?
Deduce the value of the unknown in:
x + 13 = 21
34 = x - 10