# The area of a rectangle of length x is given 3x^2 +5x. Find the width of the rectangle.

## Question:

The area of a rectangle of length x is given {eq}3x^2 +5x {/eq}. Find the width of the rectangle.

## Rectangular Area:

The polygon called the rectangle has two longer sides or lengths that are opposite each other that form right angles with the shorter sides or widths. The area of the rectangle is the product of the length and the width such that {eq}A= lw {/eq}

## Answer and Explanation:

The area is given by the expression {eq}3x^2 +5x {/eq} and the length is denoted by {eq}x {/eq}. To determine the width, use the given information in the formula for the area:

{eq}\begin{align} A &= lw \\ 3x^2 +5x &= xw \\ \dfrac{xw}x &= \dfrac{3x^2 +5x}x \\ w &= \dfrac{x(3x +5)}x \\ w &= 3x +5 \end{align} {/eq}

The expression of the width of the rectangle is {eq}w = 3x +5 {/eq}.

#### Learn more about this topic:

Measuring the Area of a Rectangle: Formula & Examples

from Geometry: High School

Chapter 8 / Lesson 7
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