-9/15y+3/21=5/15y-14/21
Move 5/15y to the other side. Sign changes from +5/15y to -5/15y
-9/15y-5/15y+3/21=5/15y-5/15y-14/21
-14/15y+3/21=-14/21
Move 3/21 to the other side. Sign changes from +3/21 to -3/21.
-14/15y+3/21-3/21=-14/21-3/21
-14/15y=-14/21-3/21
-14/21-3/21=-17/21
-14/15y=-17/21
Multiply both sides by -15/14
-14/15y(-15/14)
Cross out 15 and 15, divide by 15 then becomes 1
Cross out 14 and 14, divide by 14 then becomes 1
1*1*y=y
-17/21*-15/14
Cross out 15 and 21 , divide by 3. 15/3=2, 21/3=7
17/7*5/14=85/98
Answer: c. y=85/98
