SOLUTION: Find the dimensions of a rectangle whose width is 7 miles less than half its length and whose area is 160 square inches.

Algebra ->  Rectangles -> SOLUTION: Find the dimensions of a rectangle whose width is 7 miles less than half its length and whose area is 160 square inches.      Log On


   

Question 211555This question is from textbook Beginning & Intermediate Algebra
: Find the dimensions of a rectangle whose width is 7 miles less than half its length and whose area is 160 square inches. This question is from textbook Beginning & Intermediate Algebra

Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
LW=AREA
W=L/2-7
L(L/2-7)=160
L^2/2-7L=160
(L^2-14L)/2=160
L^2-14L=160*2
L^2-14L=320
L^2-14L-320=0
L+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
L=(14+-SQRT[-14^2-4*1*-320])/2*1
L=(14+-SQRT[196+1280])/2
L=(14+-SQRT[1476)/2
L=(14+-38.42)/2
L=(14+38.42)/2
L=52.42/2
L=26.21 ANS.
W=26.21/2-7
W=13.105-7
W=6.105 ANS.
PROOF:
26.21*6.105=160
160~160