The length of a rectangle is 2 cm more that 5 times it's width. If the area of the rectangle is 84 cm^2 find the dimensions of the rectangle to the nearest thousandth.

Question

This is what I have..is it rihgt?
5x^2+5x+2-84
5x^2+5x-82=0

-5+-the square root of 5^2-4(5)(-82)/2(5)
-5+- the square root of 25+1640/10
-5+- the square root of 1665/10
L=2+5x
L=2+5(3.58)
L=20.06 cm
W=3.58 Cm

Answer 1

I don't know how you got your equation.
let the width be x
then the length is 5x+2 and
x(5x+2)=84
5x^2 + 2x - 84 = 0

now solve that.
(Igot x=3.9 and a negative x value)