math 8th grade
posted by Anonymous .
if length and width of a 3in. x5 ln. photo are tripled what scale factor relates the area 3,9,12,27 i answered 27 is this correct i tried 9 but got no answer

recall that area of rectangle (shape of the photo) is given by
A = length * width
substituting,
A (original) = 3 * 5 = 15
if we triple both length and width,
new length = 3 * 5 = 15
new width = 3 * 3 = 9
thus,
A (new) = 15 * 9 = 105
to get the ratio, we divide the new area by original area:
105 / 15 = 9
hope this helps~ :)