What is

7x+12=13x-21

X=5.5

7x + 12 = 13x - 21

-12 - 12

7x = 13x - 33

-13x - 13x

-6x = - 33

Dived - 6 on both sides, the six cancels out and - 33 dived by - 6 is 5.5, it is a positive number because when diving two negative numbers it results in a positive number.

5 1/2 = x

Step-by-step explanation:

7x+12=13x-21

Subtract 7x from each side

7x+12 - 7x = 13x-7x-21

12 = 6x-21

Add 21 to each side

12+21 = 6x-21+21

33 = 6x

Divide by 6

33/6 = 6x/6

11/2 = x

Changing to a mixed number

5 1/2 = x