That has three sides. We solve for x in the middle side:

   -7 < 3 - 2x < 13

Add -3 to all three sides to cancel
away the 3 in the middle


   -7 < 3 - 2x < 13
   -3  -3        -3 
  ------------------
  -10 <   -2x  < 10

Now we divide all three sides by -2.
But we must remember that when we divide
by a negative number, the symbols reverse:

  -10      -2x     10
 ----- >  ----- > ---- 
  -2       -2      -2

    5  >    x   >  -5

And that is the same thing as

    -5 < x < 5

Sometimes that is written as (-5, 5),
called "interval notation".

Edwin