20
Step-by-step explanation:
Let's start by rewriting the second equation in terms of "x":
Subtract y from both sides:
Now, substitute "5-y" for "x" in the first equation:
Note that:
Cancel out like terms:
Subtract 25 from both sides:
Divide both sides by -10
Now, substitute this value back into either of the equations to solve for x.
Add 15/2 to both sides:
Now, find the difference: