The area of a rectangle is 63ft ^2 and the length of the rectangle is 5ft more than double the width. find the dimensions of the rectangle.

Define Length and Width

Let the width be x
Width = x
Length = 2x + 5


Form equation and solve for x

x(2x + 5) = 63
2x² + 5x = 63
2x² + 5x - 63 = 0
(x+7)(2x-9) = 0
x = -7 (rejected, length cannot be negative) or 2x - 9 = 0
2x - 9 = 0
2x = 9
x = 9 ÷ 2 
x = 4.5 ft


Find Length and Width

Width = x = 4.5 ft
Length = 2x + 5 = 2(4.5) + 5 = 14 ft


Width = 4.5 ft , Length = 14 ft

Choice B.  A linear equation is an equation between two variables that gives a straight line when plotted on a graph.  One variable is each day, the other is the increasing amount.  One would be the x-axis, the other would be the y-axis.