In the adjoining figure, △FGH and △QPR are
similar by AA similarity criterion
similar by SAS similarity criterion
similar by SSS similarity criterion
In △ FGH,
∠F=180∘−(∠G+∠H)∠F=180∘−(20∘+30∘)∠F=130∘ In ΔFGH and ΔQPR, ∠F=∠Q=130∘ FGPQ=637=91 FHQR=455=91
⇒FGPQ=FHQR
Hence, △FGH∼△QPR by SAS similarity.
Two triangles are similar by SAS similarity if,