Enter the number that belongs in the green box.

BA and CD are congruent. As are AM and MC so if AM = 5 then so does MC. 5 + 5 = 10. So if BD = 17, you can subtract AC from it to get BA. 17 - 10 = 7. And because BA and CD are congruent, CD also equals 7

CD = 7

sounds & other waves originate from any vibrating object

assuming this is from a math graphing problem.

7 would be on the x-axis which is the horizontal line on the graph

84 would be on the y-axis which is the vertical line on the graph