What is the measure of angle 2 ?​

The solution set for 5v2 – 125 = 0 is

Pyotr tchaikovsky sporting goods operates on a 45% overhead based on the selling price, which results in an overhead of $65.34 on the newest version of an air hockey game set. if the air hockey game set costs pyotr tchaikovsky sports $49.32, find the selling price, the markup, and the net profit.

Given the two similar triangles, how do i find the missing length? if a=4, b=5, and b'=7.5 find a'