Alberta Free Tutoring And Homework Help For Math 20-1

  0

0 Tutors Online Right Now

The length of a rectangle is 6 cm more than the width, and the area is at least 91cm2. What are the possible dimensions of the rectangle?

5 years ago

Answered By Corey A

Set Up an Aera formula for a rectangle:

Area = lw

width is some measurement, and length is that measurement + 6, l=w+6.  Area is at least 91 cm, so an inequality is necessary.  Substitute everything in:

91<w(w+6)

91<w2+6w

0<w2+6w-91

This quadratic can be factored

0<(w+13)(w-7)

So our two solutions are:

-13<w (Extraeous root because you cannot have a negative width of a rectangle)

7<w 

So the width would have to be at least 7cm and the legth would have to be at least 13cm in order to have a rectagle with an area of at least 91cm2