Solve the following equations:7 – 5x = 3x + 31

Question

a) Solve the following equations: 7 – 5x = 3x + 31

Answer 1

You need to have the x terms on one side of the equation, and the number terms on the other. Start by adding 5x to both sides.

7 - 5x  =  3x + 31
   +5x     +5x
_________________
     7     =  8x  + 31

Now subtract 31 from both sides, so that you have x terms on the right and numbers on the left:

      7     =  8x + 31
    -31               -31
  _______________
    - 24    =  8x

Now divide both sides by 8.

     x = -3

Check the answer by plugging -3 back into the original. 

7 - 5(-3) = 3(-3) + 31

7 + 15  =  -9 + 31

22  =  22