The width of a rectangle is 6 less than twice its length. If the area of the rectangle is 102 square centimeters, what is the length of the diagonal?

Question

Note: Your answer must be a number accurate to two decimal places.

Answer 1

Blade,

 

Write your width W as W = 2L-6.  We know that the area of a rectangle is L x W = Area, so substitute your expression for the width in the formula for area to solve for L.  Once you have L you should be able to immediately determine the value of W.

 

Since the sides of a rectangle are at 90° to one another they, along with the diagonal for a right triangle.  You can then use the Pythagorean Equation, a² + b² = c², to solve for the length of the diagonal.