how do you get the problem equation
To find a number which is nine less then twice the additive inverse, we will need the following fact: if x is a number, then its additive inverse is defined to be -x (because x+(-x)0). Example, the additive inverse of the number 9 is -9. We need to take two times the additive inverse of x, 2(-x), and then subtract 9 to get the number x back again. So, in the english language, x is equal to 2 times -x minus 9. Or, in the algebra language x2(-x)-9. Now, to simplify a little, 2(-x) is equal to -2 x, and so the equation x2(-x)-9 is same as the equation x-2x-9. We can solve for x: to do so, we must move x to one side of the equation, and get everything else to the other side. x-2 x -9 becomes 2 x + x -9 which becomes 3 x -9. To solve for x, we divide both sides of this last equation by 3 to get x by itself on the left of the equation, and a number on the right side of the equation. That is, we divide 3 x by 3 to get x on the left, and divide -9 by 3 to get -3 on the right and we discover that x -3.
