Consider the following:

We can form a simple equation to represent the total number of apples as:

which can also be written as:

which can also be written as:

When we take the + 120 to the other side of the equation, the sign changes to minus (-) becoming - 120. The + and − signs change to the other when moved to either side of the equation.

Newton had p mangoes.

Total number of mangoes was 45.

14 + p = 45.

Tuesday: y bags

Total: 210 bags

90 + y = 210

Ate: 4 mangoes

Arrived with 6 mangoes

k - 4 = 6.

The above equation can also be written as:

#### Practice Example 1:

We can form a simple equation to represent the total number of apples as:

**4 + 5 = b**which can also be written as:

**b = 4 + 5**#### Practice Example 2:

The number of boys in a school is n. The number of girls in the same school is 120. If the total number of student in the school is 330, form a simple equation that can be used to find the value of n.##### Answer:

**n + 120 = 330**which can also be written as:

**n = 330 - 120**

__Note__When we take the + 120 to the other side of the equation, the sign changes to minus (-) becoming - 120. The + and − signs change to the other when moved to either side of the equation.

#### Practice Example 3:

John had 14 mangoes and Newton had p mangoes. If the total number of mangoes they had was 45, form a simple equation that can be used to find the value of p.##### Answer:

John had 14 mangoes.Newton had p mangoes.

Total number of mangoes was 45.

14 + p = 45.

**p = 45 - 14**#### Practice Example 4:

The number of bags of beans harvest on Monday was 90. On Tuesday, y bags of beans were harvested. If the total number of bags harvested on Monday and Tuesday was 210, for a simple equation to show the number of bags harvested on Tuesday.##### Answer:

Monday: 90 bagsTuesday: y bags

Total: 210 bags

90 + y = 210

**y = 210 - 90**#### Practice Example 5:

A grade 5 pupil in your school bought k mangoes from the market. On his was home, he ate 4 mangoes. If he arrived home with 6 mangoes, form a simple equation to show how many mangoes he bought from the market##### Answer:

Total number of mangoes: kAte: 4 mangoes

Arrived with 6 mangoes

*If we subtract the number of mangoes he ate, from the total number of mangoes, we get the number of mangoes he was left with.*

The above equation can also be written as:

**k = 6 + 4**