Question

The area of a rectangle is 20 square inches. If the length is 4 inches less than 6 times the width, then find the dimensions of the rectangle.

Answer 1

Step-by-step explanation:

Let the width=x

Length =6x-4

As we know that in a rectangle

${\boxed{\sf Area=LB}}$

• Substitute the values

$\hookrightarrow\sf x (6x-4)=20$

$\hookrightarrow\sf 6x^2-4x=20$

$\hookrightarrow\sf 6x^2-4x-20=0$

• Here a=6, b=-4, c=-20.
• use quadratic formula

$\hookrightarrow\sf x=\dfrac {1}{3}+\dfrac {1}{3}\sqrt {31} \quad or \quad \dfrac {1}{3}+\dfrac {-1}{3}\sqrt {31}$