Hello any one out there can you please help me out with this problem and Thank you in advance.

Question

!.x+y=34
x-y=20

2.-7x+6y=11
-5x+9y-11

Answer 1

#1
Since y = 34-x,
x-(34-x) = 20
2x = 54
x = 27
y = 7

#2
There's a typo. If you meant to say
-5x+9y = 11,
do a little multiplying to get rid of y:
-21x+18y = 33
-10x+18y = 22
-11x = 11
x = -1
y = 2/3

If it was -5x+9y = -11, then
x = -5
y = -4

Answer 2

Thank you so much.