How do you solve #15x + 9= 3x - 3#?

1 Answer
Nov 10, 2016

x= -1

Explanation:

First, you have to group the x terms. To do that, you can subtract 3x or 15x from both side, either way they give you the correct answer, but I like to keep things positive whenever I can. Now that you subtracted, you can simplify into 12x+9=-3.

Second step is to do the opposite of P.E.M.D.A.S and in this case, we would need to subtract 9 so we can isolate x. Subtracting 9 on both sides can be simplified to 12x=-12.

Third, and last, step! Isolate x. Because we are doing opposite orders of operations, we divide 12 on both sides. Simplify that and get x= -1.

If you don't believe me, try checking your work by plugging the x value into the equation. You can see that the equation is true and valid so you know this is the correct solution.