Angles A and P are marked congruent; angles B and Q are marked congruent, so the triangles are similar by the AA similarity postulate. The similarity statement can be written ...
ΔABC ~ ΔPQR by AA similarity
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The ratio of sides of PQR to ABC is the ratio QR/BC = 12/6 = 2. That is, each side in the larger triangle is 2 times the length of the corresponding smaller side.
She can arrange them in the following; 1 row of 36 2 rows of 18 (doesnt count because it says other and this has already been mentioned) 3 rows of 12 4 rows of 9 (doesnt count because it says other and this has already been mentioned) 6 rows of 6
