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can anyone explain the difference between ( i will just use these numbers as examples) -27 4/3 and (-27) 4/3 I am getting confused when the difference is when the number is just negative and when there are parenthesis around it I see both as -27\frac{4}{3}=\frac{-27\cdot4}{3}=-\frac{108}{3}=-36 or ...

MOUSETAILS wrote:i think i typed it wrong here is a better example of what i am confused with:

-9^2

(-9)^2

$-9^2=-(9^2)=-(9\cdot9)=-81$

$(-9)^2=(-9)(-9)=81$

farmer has a total of 21 cows and chickens.togteher the animals have a total of 54 legs.how many cows and how many chickens does the farmer have? i got 15 chickens & 6 cows.how do u do the math 2 get the ans? let x be the number of cows let y be the number of chickens then x+y=21 and the number...

aretuta wrote:Help.
I'm having trouble solving this one.

x2-12xy+36y2

$-6+-6=-12$ and $(-6)\cdot(-6)=36$

so $x^2-12xy+36y^2=(x-6y)(x-6y)$

the trick where you get \sqrt{2x}=x only works if we know that the original sequence of numbers converges. Therefore, before one uses this technique you should determine if it converges first then use the 'trick'. Otherwise you could get the wrong answer. Also, there is only one solution to the prob...

http://www.purplemath.com/modules/ineqsolv.htm

babyZ wrote:i am stuck the question is, Find a quick, easy method to compute the first 100 number, from 1 to 100. I can`t use a calculator as a metod for this problem

What do you mean by 'compute the first 100 number'?

I'm not sure, but this is my thinking so far... If you imagine removing the circle from the middle and sliding the parabolas toward each other, their symmetry tells you that they will touch (be tangent to each other) along the line y = x. This means that their slopes will have to be m = 1 at the po...

maggiemagnet wrote:Steven went to a restaurant whose menu featured four appetizers, five salads, three entrees, and four desserts. How many different combinations could he order if a dinner included one of each item?

It's just 4*5*3*4, right? Thank you.

yes

nicknation wrote:I would like to know what the fraction is for the decimal .151515 (the 15 keeps on going )?

let x=.1515...

then 100x=15.1515...

subtract x from 100x

100x=15.1515...
- x=.1515...

99x=15
x=15/99

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