another problem

mattoram

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Sep 12, 2005
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the value of c is the value of a to the power of 2 +b to the power of 2 when a=2 and b=-2. find the value of c to the power of 2 -4.

thanks again :)
 
Do you mean the following?

. . . . .Let c = a<sup>2</sup> + b<sup>2</sup>.
. . . . .Find c<sup>2</sup> - 4 when a = 2 and b = -2.

Please reply with correction or confirmation. When you reply, please show how far you've gotten. Thank you.

Eliz.
 
Eliz

did the problem out but ended with the wrong answer..answer supposed to be 60.

problem again as it is written out in the book...the value of c is the value of A(to the power of 2)+b (to the power of 2) when a=2 and b=-2...find the value of c (to the power of 2)-4

I thought you work the problem out 2( to the power of 2) plus -2( to the power of 2) ..so thats 4 +-4 giving you -1...then from there that -1 would stand for C...so I did -1 (standing in for c) to the 2nd power -4....so I did
-1-4 and that doesn't give me the answer even close to 60.

I hope you understand!!! :)
 
Re: Eliz

Since you have not corrected what I posted, I will assume that I guessed your meaning correctly.

mattoram said:
...2( to the power of 2) plus -2( to the power of 2) ..so thats 4 +-4....
No: all squares are positive.

. . . . .3<sup>2</sup> = 3 × 3 = 9

. . . . .(-3)<sup>2</sup> = (-3)(-3) = 9

You cannot square -2 and get -4.

Eliz.
 
You would set the problem up like this:

c=a^2+b^2

when a=2 and b=-2

subsitute in 2 and -2 for variables a and b

you get c=4+4

c=8

Then is says c must be squared so if c=8 then square 8, which is 64, at the end of the problem it says -4, this leaves you with the correct answer 60. Hope this helps!
 
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