SOLUTION: the length of this rectangle is 1cm more than it's width. it has an area of 426cm² find the width correct to one decimal place

Algebra ->  Rectangles -> SOLUTION: the length of this rectangle is 1cm more than it's width. it has an area of 426cm² find the width correct to one decimal place      Log On


   

Question 736995: the length of this rectangle is 1cm more than it's width. it has an area of 426cm² find the width correct to one decimal place
Answer by checkley79(3341) About Me  (Show Source):
You can put this solution on YOUR website!
AREA=LW
L=W+1
426=(W+1)W
426=W^2+W
W^2+W-426=0
W+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
W=(-1+-SQRT(1^2-4*1*-426))/2*1
W=(-1+-SQRT(1+1704)/2
W=(-1+-SQRT1705)/2
W=(-1+-41.29/2
W=(-1+41.29)/2
W=40.29/2
W=20.1 ANS.
L=20.1+1
L=21.1 ANS.
PROOF:
426=21.1+20.1
426=425.2