Given that ∠x ≅ ∠d, and de ≅ xw, what is the third congruence needed to prove that δxwy ≅ δdec by asa?

Given that ∠X ≅ ∠D, and DE ≅ XW

To prove that ΔXWY ≅ ΔDEC by ASA

One angle and one side are congruent already so you need one more angle to prove both triangles congruent by ASA.

Answer

∠W ≅ ∠E

you didn't post any answer choices, so its not 100% clear what your teacher is looking for

however, log(15/7) is equivalent to log(15) - log(7)

i'm using the rule log(x/y) = log(x) - log(y)