A rectangular advertising banner must have an area of
MATHEMATICS · Multi-part · AoPS · Mathematics · One-Variable Linear Equations · One-Variable Linear Equations
Problem
A rectangular advertising banner must have an area of 18m2. Its width is fixed at 1.2m to fit a roadside frame.
(a) Let the required length of the banner be lm. Write a linear equation in one variable that represents the given information.
(b) Solve the equation to determine the length l.
(c) A second banner of the same width is needed to cover 24m2. Without starting a new solution from the beginning, use the value of l obtained in part (b) to find the corresponding length for the second banner and explain your reasoning.
(d) Show that your result in part (c) is consistent with solving the equation 1.2l=24 directly.