sum and difference

Question

sum of 11 and difference of 5

Answer 1

x+y=11

x-y=5

If you add those two equations together, the y eliminates and you get

2x=16

Divide both sides by 2

x=8

Then substitute x=8 into the first equation to solve for y

8+y=11

Subtract 8 from both sides

y=3