In the figure, if ∠B=∠Q, then:
△ABC∼△PQR
△ABC∼△RQP
△CBA∼△QPR
In △ABC and △PQR ABPQ=BCQR=21 ∠B=∠Q Therefore, △ABC∼△RQP by SAS similarity.
In the given figure, if ∠B=∠Q, then _____.
In the figure, PQ|| AB and PR|| BC. If ∠QPR=1020, Determine ∠ABC. Give reasons.