Question

2x-y=17
X-y= 10
Using the elimination method

Answer 1

easy just subtract 2x from each side then divide

Answer 2

2x-y=17
x-y=10

2x-y=17
-2(x-y)=-2(10)  
-2x+2y=-20
(cross out the -2x's)
-y=17
+2y=-20
y=3
(plug 3 into y to find x)
(3)-y=10
-y=7
y=-7
x=3 & y=-7