Posted by nabiha on Tuesday, April 20, 2010 at 5:15pm.
let the height be h
then width is h+5
solve h(x+5) = 80 as a quadratic
but how do u solve h(x+5)=80
i have never come across ones like these.
should have been
h(h + 5) = 80
h^2 + 5h - 80 = 0
using formula
h = (-5 ± √ 345)/2
= 6.78 or some negative number
so height is 6.78
width = 11.78
area = 6.78x11.78 = 79.87
don't know what accuracy you needed in the answer.
Related Questions
maths - The width of a rectangular photograph is 5cm more than the height. The ...
Math - The area of a rectangular photograph is 59 square inches.It is to be ...
Algebra - Posted by bailey on Monday, January 8, 2007 at 2:12pm. The area of a ...
geometry - calculate the area, surface area, and volume for a right rectangular ...
math - what is the surface area of a rectangular prism with the width 4cm lenth ...
Math - If a rectangular box has A width of 2cm, a length of 3cm, and a height of...
math - The ratio of height of an object in a photograph to the actal height is 1...
math - Suppose a rectangular box with 3cm height, 2cm width, and 5cm length was...
math - A rectangular poster has an area of 190in(squared). The height of the ...
geometry - The surface area of a right rectangular prism is 112 sq units. The ...
For Further Reading
