which additional fact proves that δrst and δwxy are congruent if ∠r ≅ ∠w and rs ≅ wx.

∠r = 2x + 3
∠s = x + 10
∠t = 3x - 13
a) ∠x = x + 33
b) ∠y = x + 33
c) ∠x = 2x - 20
d) ∠y = 2x - 20