Andres F. | Great Mathematician, Math Genius, Great teacher & tutorGreat Mathematician, Math Genius, Great ...

4.84.8(88 lesson ratings)(88)

1

-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

Darin B. | Experienced English, Social Studies, and Math TutorExperienced English, Social Studies, and...

1

It may also be helpful to reorganize the problem. Because this equation only involves subtraction and addition, you can regroup the equation by like terms.