State which pairs of triangles in Fig. are similar.Write the similarity criterion used by you for answering the question and also write the pairs of similar triangles in the symbolic form:







(i) From the figure:

A = P = 60°


B = Q = 80°


C = R = 40°


Therefore, ΔABC ΔPQR [By AAA similarity]



(ii) The triangles ABC and QRP are similar to each other by SSS similarity


(iii) The given triangles are not similar because the corresponding sides are not proportional


(iv) In triangle MNL and QPR, we have



M = Q = 70o


ΔMNL ~ ΔQPR (SAS similarity)


(v) In triangle ABC and DEF, we have


AB = 2.5, BC = 3


A = 80o


EF = 6


DF = 5


F = 80o



And,


B ≠ F


Hence, triangle ABC and DEF are not similar


(vi) In triangle DEF, we have


D + E + F = 180o (Sum of angles of triangle)


70o + 80o + F = 180o


F = 30o


In PQR, we have


P + Q + R = 180o


P + 80o + 30o = 180o


P = 70o


In triangle DEF and PQR, we have


D = P = 70o


F = Q = 80o


F = R = 30o


Hence, ΔDEF ~ ΔPQR (AAA similarity)


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