PLS HELP ASAP!!
Shaylynn has a square poster of a puppy on her bedroom wall. The width is one-third the length of the picture. If the width is 21 inches, write and solve an equation to determine the length.
A) 3L = 21; L = 7 inches
B) 3 + L = 21; L = 18 inches
C) L − 3 = 21; L = 24 inches
D) L over 3 equals 21; L = 63 inches
