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Psychguy98

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c = a^2 + b^2/(ab) In the equation, a and b are positive numbers. If the values of a and b are each multiplied by 10, what is the corresponding change in
the value of c?

So I can start by plugging in 10?
 
Did you mean what you have written

\(\displaystyle a^{2} + \frac{b^{2}}{a\cdot b}\)

or this

\(\displaystyle \frac{a^{2}+b^{2}}{a\cdot b}\)

In any case, the direct answer to your question is "no".

Just like the last one, use a creative substitution and see what happens.

I would try 10*A = a and 10*B = b, do a little algebraic simplification and see if any magic occurs.

Rather than a purely algebraic solution, you could experiment a little. Try a = b = 1 and see what yuo get. Then try a = b = 10.

Answers don't always jump out at you. Feel free to explore. You can't break it. :wink:
 
Also, please think carefully on Order of Operations. This will help you communicate accurately. In addition, it is an "expression", not an "equation". It does matter if you wish to be understood on the first try without explanatory questions.

Let's see what you get. You might be surprised by this one.
 
Psychguy98 said:
wouldn't it be 10a^2 + 10b^2/ 10ab ?
Click to expand...

Absolutely not. For one, you failed to repair your notation. Try this. (10a^2 + 10b^2) / 10ab -- See how that puts the intended numerator together?

This is what I am talking about when I address being understood on the first attempt. You did not say what you were doing. You stuck a couple of 10s in there. What were you trying to do? Tell us what you are doing and we will understand it. Throw stuff out and no one will get it.

For a = b = 1, we have (1^2 + 1^2)/(1*1) = (1+1)/1 = 2/1 = 2

Now, you do a = b = 10
 
Psychguy98 said:
100a^2 + 100b^2/ 100ab
Click to expand...

Again, you just did not tell us what you were doing. Whether it's correct or not, no one can compare it to what you were thinking unless you tell us. Yet again, you failed to fix the notation. Write what you mean! Don't make your audience guess.

How did you get that? What are you trying to do with it? Does it answer the question?

By the way, it's traditional (and often necessary) to reduce fractions to lowest terms.
 
Psychguy98 said:
wouldn't it be 10a^2 + 10b^2/ 10ab ?
Click to expand...
No.
Even if it was, BRACKETS required: (10a^2 + 10b^2) / (10ab) ; are you omitting them on purpose? :shock:

If you're multiplying a and b by 10, then:
[(10a)^2 + (10b)^2] / [(10a)(10b)]

Edit: whoops, sorry to interfere...carry on TK...
 
For a = b = 1, we have (1^2 + 1^2)/(1*1) = (1+1)/1 = 2/1 = 2

for a = b = 10 we have ( 10^2 + 10^2)/(10 *10) = (10 +10)/10 = 1
 
c = (10a)^2 + (10b)^2/ (10a)(10b) = 100a^2 + 100b^2/100 ab

They have to cancel out?
 
Re:

mmm4444bot said:

I think Psychguy98 is BigGlenntheHeavy.
Click to expand...
Ya, I'm beginning to wonder also...
Look at his equation right before your post:
c = (10a)^2 + (10b)^2/ (10a)(10b) = 100a^2 + 100b^2/100 ab
Still no brackets: should be (100a^2 + 100b^2) / (100 ab)
He must have been told 1000 times (feels like that!) about this...
 
If that were the case and could be established, then another banning would be possible.
 
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