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tinkgirl1
Oct 2, 2007, 06:31 PM
I'm really confused as to what I do in these types of problems can you help me for example.
:confused: the squareroot of 7 divided by the 5square root of 7 so s √7 / 5√7 help!!

bignaked101
Oct 2, 2007, 07:06 PM
Well, first you need to do the second equation first, remember PEMDAS? (Parentheses, Exponents, Multiplication, Division, Addition, and Subtraction) or in other words, That Order Of Operations. Well this is pretty much it... Do the Division first, 5x√7 the square root of 7 is 2.65 (2.6457513), Now multiplying that by 5 would be 13.23 (13.228756), now that you have that, just divide 2.65 or 2.6457513 by 13.23 or 13.228756 and you will get your answer, simple algebra!

The equation broken down for you would be:

2.65 / (5 x 2.65)

that would be:

2.65 / 13.23

And there is the equation totally broken down there..

Answer: 0.2

derobert
Oct 7, 2007, 01:37 PM
Actually, this is isn't a problem requiring a calculator, annoying decimal multiplication, etc. In very drawn out steps:

\frac{\sqrt{7}}{5 \sqrt{7}} = \frac{1 \sqrt{7}}{5 \sqrt{7}} = \left(\frac{1}{5}\right) \left(\frac{\sqrt{7}}{\sqrt{7}}\right) = \left(\frac{1}{5}\right) \left(1\right) = \frac{1}{5}

Which is, of course, the same 0.2 that the other respondent got, but with much less work (normally, you'd not write all those steps — just the first and last).