geometry
posted by evadahun .
in the given figure,PQ=PS and QR=SR.Prove that triangle PQR is congruent to triangle PSR.

Sorry  no figures here. Describe the triangles, if possible.
If they're right triangles, it's possible that SAS will justify the assertion. 
Describe the triangles. If PR is a common side to each triangle, then SSS congruency will work.