Question

Sally has a photograph that has an area of 35 square inches. She creates 2 enlargements of the photograph. The enlargements have areas of 140 square inches and 560 square inches. In each photograph, the length is 1 2/5 times the width. Select which of thr following could be th dimensions of the original photograph or one of the enlargements. Mark all that apply

5 inches by 7 inches
20 inches by 28 inches
7 inches by 20 inches
21 inches by 15 inches
10 inches by 14 inches

Answer 1

The area of the photograph is:
A = (w) * (l)
Where,
w: width
l: long
Substituting:
35 = (w) * (1.4w)
35 = 1.4 * w ^ 2
w = root (35 / 1.4)
Dimensions of the original photograph:
w = 5 in
l = 1.4 * (5) = 7 in
Dimensions of extension 1:
k = (140) / (35) = 4
w = 4 * 5 = 20 in
l = 4 * 7 = 28 in
Dimensions of extension 2:
k = (560) / (35) = 16
w = 16 * 5 = 80 in
l = 16 * 7 = 112 in

Answer:
5 inches by 7 inches
20 inches by 28 inches