Problem: Given rectangle R1​ with one side 2 inches and area 12 square inches. Rectangle R2​ with diagonal 15 inches is similar to R1​. Expressed in square inches the area of R2​ is:
Answer Choices:
A. 9/2
B. 36
C. 135/2
D. 910​
E. 2710​/4
Solution:
The sides of R1​ are 2 inches and 6 inches and the square of its diagonal, d2, equals 62+22(=40) Since the rectangles are similar, we have
area R1​ area R2​​=d2D2​∴ area R2​=40225​.12=2135​