Sorry the first 2 times I tried answering it wouldn’t send and then deleted my responces :’)
Finding X:
3x-y=23
2x+y=17 (add the 2 equations)
5x=40
5x/5=40/5
X=8
To Find Y:
Take one of the equations from above and replace X with 8
2(8)+y=17
16-16+y=17-16
Y=1
To Check we can take the other equation and replace X and Y with what we got
3(8)-1=23
24-1=23
23=23