Q2 of 70 Page 120

For ΔPQR and ΔXYZ, the correspondence PQR ↔ YZX is a similarity. m∠P = 2m∠Q and m∠X = 120. Find m∠Y.

Given, ΔPQR and ΔXYZ

P = 2Q and X = 120


If the correspondence PQRYZX is a similarity then


m∠P = m∠X ... (i)


m∠Q = m∠Y ... (ii)


m∠R = m∠Z ... (iii)


From eq. (i) and (ii)


∠P = 120


Because mP = 2mQ


Hence, 2Q = 120


Q = 60


And ∠Q = ∠Y


Hence, ∠Y = 60.


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