(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

(5R^{2}+11)^{1/2}=-4R

(It's actually written as a squareroot rather than being raised to the 1/2 power, but couldn't get latex to do it's thing.)

2. Relevant equations

None?

3. The attempt at a solution

I tried a couple different ways, none yeilding the correct answer. eg:

Squaring both sides to get

5R^{2}+11=16R^{2}

Combining like terms (16R^{2}-5R^{2}) to get

11=11R^{2}

Without going any further, I can already tell that this is the wrong answer. Continuing, I'll get 1 rather than -1 (the solution when I solve graphically, also in the back of the book)

I also tried to begin by dividing both sides by -4. That didn't really get me anywhere.

Edit: I thought I should elaborate on that...

Dividing by -4

[(5R^{2}+11)^{1/2}]/-4=R

Getting R by itself doesn't really change anything for me. I still need to "get rid" of the square root. It also gives me an unpleasant fraction to work with. I'd rather not go that route if I don't have to.

I've got some kind of mental block that won't let me see what I'm doing wrong. You don't have to give me all the steps to solve the problem, maybe just tell me what I did wrong and point me in the right direction.

Thanks in advance.

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# Homework Help: Help with a power equation

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