Why?The area of a square is represented by (9z² - 12z + 4) ft². Which expression represents the perimeter of the square?
My answer was A - (3z-2) ft, but the correct answer was B - (3z+2) ft.
Why?The area of a square is represented by (9z² - 12z + 4) ft². Which expression represents the perimeter of the square?
My answer was A - (3z-2) ft, but the correct answer was B - (3z+2) ft.
The answer is wrong.
STOP PM'ING ME
This looks hard..
How do you do it? can you 'unsquare'? lol
Edit:
lol... i came up with -12z + 8
Edit:
Not that i only think the perimeter was only one-sided (funny joke), but i think the people who made the answer messed up -2*-2 when doing a reverse foil or similar method. That's my theory.
Last edited by Mushini; 03-19-2012 at 09:11 AM.
Triggers..
whichever one increases faster in the direction of it's limit and is not negative is the answer.. side lengths can't be negative..
iunno :S both seem right to me..
Perimeter is 4 sides.. those 0's represent only 1 side.. so times it by 4..
12z + 8 = y
12z - 8 = y
limit as x -> -inf for 12z + 8 = -inf pos slope always
limit as x -> +inf for 12z + 8 = + inf faster increase than the -8 counter part. -8 counter part always has -slope :S
Iunno.. this seems like a troll question.. there is no answer -_-
I am Ggzz..
Hackintosher
No tricks or troll.
It's my sisters HW problem, she is 12 years old.
Simple algebra is all that's needed.
I also think she/hobbit are correct, maybe answer in book is wrong.
The correct answer is (3z-2) Proof:
(9z^2-12z+4)=(3z-2)(3z-2) (meaning (3z-2) is the length of one side of the square
(3z-2)*4=(12z-8) (because there are 4 sides to a square)
(12z-8)= (3z-2)
It's a really easy question I guess it must just be a misprint in the book or something. Get her to tell her teacher so the other kids don't get confused.
I don't know what ft means but:
sqrt(9z² - 12z + 4) = 3z-2 or -(3z-2)
sqrt(9z² - 12z + 4) = 3z-2 or -3z + 2
I believe the perimeter would be:
4 * (3z-2) = 12z-8 or 4 * (-3z+2) = -12z+8
Working on: Tithe Farmer
simple - you know that 3z-2 is length of one side so it cannot be the correct answer unless 3z-2 = 0, which would not yield square to begin with
that leaves the answer 3z+2
and of course that means we can calculate z by saying:
4(3z-2) = 3z+2
9z = 10
so there you go - the square is 1 1/3 x 1 1/3 and length of all 4 sides is 5 1/3
no misprint... just a trick question
Perfect script? There is no such thing as "perfect", only "better than you expect".
I agree with Hobbit, answer is wrong but big of a grave dig guys...
(3z - 2)^2 = (3z - 2)(3z - 2) = (3z)(3z) - 2(3z) - 2(3z) + (-2)(-2) = 9z^2 - 12z + 4
well we know the perimeter isnt 3z-2 because thats one side, and it would only work if the side was 0, then it isnt a square. the perimeter should be 12z-8 but without more info we cant know anything more about it
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