Respuesta :

texaschic101
QR = PR - PQ

QR = 13y + 25 - (8y + 5)
QR = 13y + 25 - 8y - 5
QR = 5y + 20 <==
The length of QR is the length of PR minus the length of PQ. So write out the formula:
(13y + 25) - (8y + 5) 

Expand
13y + 25 -8y - 5

Combine
5y + 20

So the length of QR is 5y + 20