I am thinking of two numbers.

When I add them

I get 15.

When I subtract

them I get 3.

What are the two

numbers?

9 and 6

Step-by-step explanation:

Write down the system.

The two numbers are x and y.

We are therefore given:

x+y=15

x-y=3

I will solve this for elimination since it is already setup for it.

I will add the columns since both equations are in the same form.

2x+0y=18

2x = 18

Divide both sides by 2:

x = 18/2

Simplify:

x = 9

So if x+y=15 and x=9, then y=6.

The two numbers are 9 and 6.

Test:

9+6=15

9-6=3