Question

The sum of two numbers is 16 and their difference is 14 what are those two numbers?

Answer 1

i believe the answer is 15. You should use a number line to solve this equation.

Answer 2

(1) x + y = 16,
(2) x - y = 14

If we subtract equation (2) from equation (1) we get:
x + y - (x - y) = 16 - 14
2y = 2
y = 1

If y = 1:
x + 1 = 16
x = 15

Therefor the two numbers are 1 and 15