Which two statements are missing in steps 3 and 4? ∠x ≅ ∠c △abc ~ △zyx by the sas similarity theorem. ∠b ≅ ∠y △abc ~ △zyx by the sas similarity theorem. startfraction a c over x y endfraction = 2 △abc ~ △zyx by the sss similarity theorem. startfraction z x over a c endfraction = 2 △abc ~ △zyx by the sss similarity theorem.