I have the math equation -9x - 13 - 9x = -31. please help.

-9x-13-9x=-31

Step 1: Add the 13 to where is the -31 to leave the x's alone like this: -9x-9x=-31+13

Step 2: Remember that when subtracting to negative numbers that the first negative stays the same while the minus sign changes to addition. Then second number has it's own negative sign like this: (-9x)+(-9x).

Step 3: Add both sides: (-18x)= -18

Step 4: Divide the -18 from x and put it under the other -18 then you will find x. Enjoy