ΔLMN ~ ΔXYZ for the correspondence LMN ↔ ZYX. If m∠Z = 50, m∠X = 40, then m∠L + m∠N =

State whether the following statements are true or false. Give reasons for your answer:

(1) If ΔPQR and ΔABC are similar and none of them is equilateral, then all the six correspondences between ΔPQR and ΔABC are similarities.

(2) All congruent triangles are similar.

(3) All similar triangles are congruent.

(4) If the correspondences ABC ↔ BAC is similarity, then AABC is an isosceles triangle.

(5) The correspondence PQR ↔ YZX between ΔPQR and ΔYZX is a similarity. If m∠P = 60, m∠R = 40, then m∠Z = 80.

ΔABC ~ ΔPQR for the correspondence ABC ↔ QRP. If m∠A = 50, m∠C = 30, then m∠R =

If the correspondence ABC ↔ EFD is a similarity in AABC and ADEF, then of the following is not true.

ABC ~ PQR is a similarity in ΔABC and ΔPQR. If the perimeter of ΔABC is 12 and perimeter of a ΔPQR is 20, then AB : PQ =