15y-8y=714
7y=714
y=714:7
y=102
9x+x=500
10x=500
x=500:10
x=50
10x+x=702
11x=702
x=702:11
x=63 9/11
6x+3x-x=6400
8x=6400
x=6400:8
x=800
6y+2y+25=65
8y=65-25
8y=40
y=40:8
y=5
