Question

Two numbers whose sum is 29 and their difference is 15

Answer 1

22 and 7

Explanation:

Let x and y be the two numbers we are looking for:

The statement “their sum is 29” means x + y = 29

The statement “their difference is 15” means x - y = 15

we get this system:

x + y = 29 (1)

x - y = 15 (2)

Let’s solve it :

(1) + (2) ⇒ x + y + x - y = 29 + 15 ⇒ 2x = 44 ⇒ x = 44/2 = 22

Now we replace x by 22 in equation (1) :

22 + y = 29 ⇒ y = 29 - 22 = 7