What is the answer for x because i got x/2- 5=4

Me. i can't figure out this question. give an explanation too. .

Find the difference in area between the circle and the triangle. click on the answer until the correct answer is showing. possible answers: a = 4 pi - 8a = 9 pi - 9/2 √3a = 16/3 pia = 16a = 27 pi

Find the value of x to the nearest tenth. a. 4.5 b. 5.4 c. 6.3 d. 7.2