SOLUTION: A large rectangular movie screen in an Imax theater has an area of 9,191 square feet. Find the dimensions of the screen if it is 10 feet longer than it is wide.

Algebra ->  Rectangles -> SOLUTION: A large rectangular movie screen in an Imax theater has an area of 9,191 square feet. Find the dimensions of the screen if it is 10 feet longer than it is wide.      Log On


   

Question 458663: A large rectangular movie screen in an Imax theater has an area of 9,191 square feet. Find the dimensions of the screen if it is 10 feet longer than it is wide.
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
width =x ft
length = x+10 feet
Area = 9191 sq.ft
Width =x ft
Length =(x+10)
Area = x*(x+10)
9191 =x^2+10 x
x^2+10x -9191 =0
Find the roots of the equation by quadratic formula

a= 1 b= 10 c= -9191

b^2-4ac= 100-36764
b^2-4ac= 36864
sqrt%28%0936864%09%29= 192
x=%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29
x1=%28-b%2Bsqrt%28b%5E2-4ac%29%29%2F%282a%29
x1=(-10+192)/2
x1=91
x2=(-10 -192) / 2
x2= -101
Ignore negative value
x = 91 feet
length = 91+10 = 101
m.ananth@hotmail.ca