Question

a photo measures 3 inches by 5 inches and needs to be enlarged to 9 inches by 15 inches. what is the scale factor? a. 3 b. 2 c. 5 d. 4

Explanation:

Step1: Define scale - factor formula

Scale factor = $\frac{\text{new dimension}}{\text{original dimension}}$

Step2: Calculate scale - factor for length

Original length = 3 inches, new length = 9 inches. Scale factor = $\frac{9}{3}=3$

Step3: Calculate scale - factor for width

Original width = 5 inches, new width = 15 inches. Scale factor = $\frac{15}{5}=3$
Since the scale factor is the same for both length and width, the scale factor of the enlargement is 3.

Answer:

A. 3