A building that is 90 feet tall cast a shadow 30 feet long what is the angle of elevation of the sun

When are two distinct non vertical lines parallel

In the diagram, the ratios of two pairs of corresponding sides are equal to prove that almn - axyz by the sas similarity theorem, it also needs to be shown that x 6 z un z zz un = 2x zləzz lezy

Prove sin2a + cos2a - 1 / sin2a + cos2a + 1 = 1 - tana / 1 + cota