To prove that △dfe ~ △gfh by the sas similarity theorem, it can be stated that startfraction d f over g f endfraction = startfraction e f over h f endfraction and ∠dfe is 4 times greater than ∠gfh. ∠fhg is one-fourth the measure of ∠fed. ∠dfe is congruent to ∠gfh. ∠fhg is congruent to ∠efd.