<u><em>21 is the correct answer. </em></u>You can also used pemdas stands for: p-parenthesis, e-exponents, m-multiply, d-divide, a-add, s-subtracting. First you had to add and subtracting from left to right, and it gave us, , , . And then apply rule, and it gave us, , or .<em><u> 21 is the correct answer.</u></em> Hope this helps! And thank you for posting your question at here on brainly, and have a great day. -Charlie