Question

Write and solve the system using any method:

Find the value of two numbers if their sum is 25
and their difference is 7.
This is a 3 part question; answer all 3 parts.
1. Write the first equation.
2. Write the second equation.
3. Write your solution

Answer 1

1. x + y = 25

2. x - y = 7

3. x = 16, y = 9

Explanation:

(x + y = 25) + (x - y = 7)

2x (the y cancels) = 32

32/2 = 16, x = 16

substitute x in either equation

16 + y = 25

y = 9