Question

The question is 7a +10 = 2a

Answer 1

 7a + 10 = 2a  subtract 2a from both sides
-2a          -2a
 5a + 10 = 0    subtract 10 from both sides
       -10    -10
5a = -10          then divide both sides by 5
/5      /5
a = - 2

Answer 2

7a+10=2a
Subtract 7a from both sides.
10=-5a
Divide 10 by -5.
-2=a or a=-2