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lostinconfusion

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Radical Expressions

1.    simplify:

3 + 3/x
----------
4 + 4/x

2.    solve for q and check the answer:

q^2                            2       =  3
------             -        _____      ____
(q^2 -16 )               (q-4)       (q+4)

3.    simplify

4 Square root of 81x^2
                           --------
                               16

The perfect square would be 9.. but the3 * 3* 3 * 3= 81 which is the square root of 81 * itself 4 times. And the numerator would be 2.. Because 2*2*2*2 = 16
But I'm not sure how to set it up etc, and my book doesn't do that great of a job explaining steps.

4.    simplify (rationalize the denominator):

square root of t
-----------------------
square root of t+3

5.    word problem (solve using an algebraic equation):

Ray works at two places, a fun job that pays only $4.50 an hour, and a high-pressure job that pays $7.00 an hour. Assuming that he can choose how many hours he works at each job in a given week, and that he plans to work a total of 40 hours this week, how many hours should he work at each job if he wants to average $6.00 an hour for the week?

I know the answer is 16 hrs at the 4.50 an hour job and 24 hrs at the 7.00 an hour job to give us an average of 6.00/hr but I have no clue how to set it up..

4.50 X + 7.00 X =  ?

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Radical Expressions

Couldn't sleep, needed something to do, so I looked at the oldies.

#1
Simplify

After multiplying numerator and denominator by x

Factoring

Cancelling

#2 Solve for q

multiply both sides by

I rejected 4 because it is undefined in the original problem, so q = 1

#3

#4

Rationalize the denomonator of:

Multiply numerator and denominator by

simplified and rationalized:

#5

You have 2 simultaneous equations.

Last edited by bobbym (2009-05-31 22:03:18)

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