At a used bookstore, the price of a hardcover book is three times the price of a paperback book. If 40 hardcover books were sold for a total of $480 and the combined sales of hardcover
and paperback books totaled $600, how many paperback books were sold?

A) 10
B) 12
C) 30
D) 40

answer is b

step-by-step explanation:

so the possibilities of the measurement of the side of the triangle are either it is longest side or not the longest side

when it is the longest side

s < 25 + 35s < 60

if it is not the longest side

35 < 25 + s10 < sso 10 < s < 60so the perimeter70 < p < 130

whaere is the picture

step-by-step explanation:

it will take 9 minutes