solve: 7=7(x+9)-2x

Question

solve: 7=7(x+9)-2x

Answer 1

First distribute the 7 on the left side of the = sign so that you have 7*x and 7*9.

You now have 7=7x+63-2x

Next do 7x-2x (since both have x) to you get 5x.

Now you have 7=5x+63

Isolate the 5x by subtractin 63 from both sides (7-63=5x+63-63) and you get -56=5x

Finally isolate the x by dividing (both sides) by 5 ---> -56/5=5x/5

This gives you the answer -11.2=x

Finally plug in 11.2 to the original problem to check your work------> 7=7(-11.2+9)-2(-11.2)

                                                                                                    7=-78.4+63+22.4

                                                                                                    7=7

NOTE: This is so much easier to show using pen and paper than trying to type out the step-by-step process on a computer:)

Answer 2

You want to isolate x to one side of the equal sign and non x values to the other side of the sign.

7 = 7x + 63 - 2x 

7 = 7x - 2x + 63        (makes it easier to work with the x or like values)

7 = 5x + 63

7 - 63 = 5x + 63 - 63       (subtract 63 from both sides of the equal sign)

-56 = 5x          (ta da! The x value is isolated to one side of the equation)

-56/5 =5x/5     (simplify for x only by dividing both sides by 5)

-56/5 = x