If the temperature outside was 63°F at 5:00 p. m., but it fell 21 degrees by 10:00 p. m., what is the temperature at 10:00 p. m.?

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