The answer is C but i don’t know why, can someone explain it please?

In triangle △abc, ∠abc=90°, bh is an altitude. find the missing lengths. ah=4 and hc=1, find bh.

A, at (-2, 4), is 6 .of a'? (-8, 4) (-8, -2) (-2, -2) (-2, 4) b, at (-4, -7), isy-.of b'? (-4, 7) (4, -7) (4, 7) (-4, -7)

Match the following reasons with the statements given to create the proof. 1. do = ob, ao = oc sas 2. doc = aob given 3. triangle cod congruent to triangle aob vertical angles are equal. 4. 1 = 2, ab = dc if two sides = and ||, then a parallelogram. 5. ab||dc if alternate interior angles =, then lines parallel. 6. abcd is a parallelogram cpcte