Answer: x = 6
Step-by-step explanation: To solve for x, we must first isolate the term containing x which in this problem is -3x.
Since 28 is being added to -3x, we subtract 28 from both sides of the equation to isolate the -3x. On the left, the +28 and -28 cancel out and on the right 10 - 28 is -18 so we have -3x = -18.
Now we can finish things off by just dividing both sides of the equation by -3. On the left the -3's cancel and we have x. On the right, -18 divided by -3 is 6 so we have x = 6 which is the solution to our equation.