Respuesta :

wegnerkolmp2741o

Answer:

7

Step-by-step explanation:

Since the triangles are similar, we can use ratios

15        21

----- = ---------

5         PR

Using cross products

15 PR = 21*5

Divide each side by 15

PR = 21*5/15

PR = 7

Answer: yes it would be 7

Step-by-step explanation: