Solving Equations Using Trial and Error

Find the method used.

x + 2 = 5

1. 1 + 2 = 3 (x)

2. 2 + 2 = 4 (x)

3. 3 + 2 = 5 (/)

x = 3

• Trial and Error Method

• Backtracking Method

• Application of Equality Concept

Methods of solving a linear equation are as follow

• Backtracking Method

• Trial and Error Method

• Elimination Method

• Application of Equality Concept

Find a suitable linear equation for the situation below :

There are a few apples in the refrigerator. Ali bought 10 more apples from the supermarket. Now, he has a total of 20 apples.

• 5 + 10 = 20

• x + 10 = 20

• x + 20 = 10

• 20 + 10 = x

Use trial and error to solve:
7x - 5 = 30

• 5

• 3

• 4

• 2

Use trial and error to solve:
4x + 10 = 22

• 5

• 3

• 4

• 2

Jill is using trial and error to solve the following equation.

She first tries 4.

Will she need to try a higher or lower number for her next trial?
3x + 6 = 21

• she got it correct usig 4

• higher

• lower

Solve the following equation using the inspection method.
x + 7 = 28

• x = 35

• x = 4

• x = 196

• x = 21

t - 0.7 = 9

• t = 9

• t = 9.7

• t = 8.3

• t = 0.7

h ÷ 3 = 4.5

• h = 1.5

• h = 13.5

• h = 7.5

• h = 1

7w = 2.1

• w = -4.9

• w = 0.3

• w = 14.7

• w - 2.8