How can I do this exercise? (-2)/(12) = (x + 1)/(x + 2)

Question

How can I do this exercise?
`(-2)/(12) = (x + 1)/(x + 2)`

Answer 1

-8/7 =x

Explanation:

-2 x+1

----- = -----------

12 x+2

Using cross products

-2 (x+2) = 12 (x+1)

Distribute

-2x -4 = 12x+12

Add 2x to each side

-2x+2x -4 = 12x+2x+12

-4 = 14x +12

Subtract 12 from each side

-4-12 = 14x

-16 = 14x

Divide each side by 14

-16/14 =14x/14

-8/7 =x