SOLUTION: (((The perimeter of a rectangle is 1100ft find the dimesnions so that the enclosed area will be 60,000 square ft)))) please help

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Question 32461: (((The perimeter of a rectangle is 1100ft find the dimesnions so that the enclosed area will be 60,000 square ft)))) please help
Found 2 solutions by Paul, checkley71:
Answer by Paul(988) About Me  (Show Source):
You can put this solution on YOUR website!
THe formula for the perimeter is:
2(l+w)=P
In this case P = 1100 and length and width are unknown.
2l+2w=1100

Solve for length:

l=550-w (subsitution)

The Area in this case is A=60000

lw=60000

Subsitute for l

(550-w)(w)=60000

-w%5E2%2B550w=60000

w%5E2-550w%2B60000=0

Factor: (w-150) or (w-400)

Remvoe the 150 x=400

l=550-400

l=150

Hence, the width is 150ft and the length is 400ft.

Paul.

Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
2X+2Y=1100 & X*Y=60000 THEREFORE 2X=1100-2Y OR X=(1100-2Y)/2 OR X=550-Y
SUBSTITUTING IN EQUATION 2 WE GET (550-Y)Y=60000 OR 550Y-Y~2=60000 OR
-Y~2+550-60000=0 OR Y~2-550+60000 OR (Y-400)(Y-150)=0 OR Y=400 THEN
X=60000/400 OR X=150 OR Y=150 THEN X=60000/150 OR X=400
PROOF 2*400+2*150=1100 OR 800+300=1100