Question

A rectangular poster has an area of 504 centimeters the width is 14 centimeters how long is the poster

Answer 1

Length(width) = area

504 = 14(x)

504/14 = 14(x)/14

x = 504/14

x = 36

the poster is 36 centimeters long

hope this helps :D

Answer 2

Let the length of the poster be l and the width be w. 
w=14
l*w=504
l*14=504
l=504/14=36 cm. Hope this helps!