Using Linear Systems

Question

two numbers total-10, and their difference is 4. Find the two numbers.

 

 

 

 

 

 

 

 

 

( answer is -3 and -7 but i need help step by step on how they got this answer)

Answer 1

This particular type of problem arises a lot.

x+y=-10

x -y=4

Add the two equations to get

2x=-6 or x=-3

Subtract the second equation from the first to get

2y=-14 or y=-7