Question

Solving linear equation 7-x=19

Answer 1

x is equal to -12
7-(-12)=19

Answer 2

x = -12

Explanation:

To solve an equation, you want to "undo" what has been done to the variable. Here, it has been multiplied by -1 and that result added to 7. In general, you want to "undo" these operations in reverse order.

First, you need to subtract 7 to undo the addition of 7. Of course, anything you do to one side of the equation is also done to the other side:

7 -x -7 = 19 -7

-x = 12 . . . . . . . . simplify

Now, you want to undo the multiplication by -1. Multiplication (or division) by -1 will take care of that:

(-1)(-x) = (-1)(12)

x = -12 . . . . . . . . simplify

The solution is x = -12.