It will equal 22.5 since you need to multiple
The answer is C.50. That is the answer.

Multiplying a positive and a negative equals a negative: (+)×(-)=(-)

Calculate the product

First divide both sides by 12 so u get 5x -4.5 = 3. Now add 4.5 to both sides and u get 5x = 7.5. Now divide 7.5 by 5 and u get 1.5