What is the value of y in the following system of equation3x-4y=-20 -x+2y=10

Alex drew a circle with right triangle prq inscribed in it, as shown below: the figure shows a circle with points p, q, and r on it forming an inscribed triangle. side pq is a chord through the center and angle r is a right angle. arc qr measures 80 degrees.

Which statement best describes the polynomial

In triangle △abc, ∠abc=90°, bh is an altitude. find the missing lengths. ac=26 and ch=8, find bh.