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rapaljer answered: 4664 problems
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Polynomials-and-rational-expressions/88205: PLease help! I tried to solve this, can't do it. Am I supposed to change the form of the problem befdore I solve it? The problem is I need to simplify as much as possible 6x^2-x-2 over 3x^2+x-2.
1 solutions

Answer 64044 by rapaljer(4667) About Me  on 2007-07-12 15:16:07 (Show Source):
You can put this solution on YOUR website!
The first problem is to FACTOR the numerator and denominator. It's like in the last solution that I posted, but this time the factoring is a LOT harder. You may need some help with what I call "Advanced Trinomial Factoring" and I have a lesson on this if you are interested.

%286x%5E2-x-2%29%2F%283x%5E2%2Bx-2%29+
%28%283x-2%29%282x%2B1%29%29%2F%28%283x-2%29%28x%2B1%29%29+

Now, the (3x-2) factors divide out:
%282x%2B1%29%2F%28x%2B1%29+

The Lesson on Advanced Trinomial Factoring can be found in algebra.com or go to my own website by clicking on my tutor name "rapaljer" anywhere in algebra.com. Next, click on "Basic Algebra", then "Samples from Basic Algebra: One Step at a Time", then in Chapter 2, look for the section about "Advanced Trinomial Factoring." While you are there, check out ALL the sections on Factoring. There are several sections devoted to this important skill.

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Polynomials-and-rational-expressions/88206: Here's another problem like the first problem. X^2-4+4 over X62-4

1 solutions

Answer 64042 by rapaljer(4667) About Me  on 2007-07-12 15:08:02 (Show Source):
You can put this solution on YOUR website!
%28X%5E2-4x%2B4%29%2F%28X%5E2-4%29

The first step is to FACTOR the numerator and denominator:
%28%28x-2%29%28x-2%29%29%2F%28%28x-2%29%28x%2B2%29%29+

Divide out the factors of (x-2):
%28x-2%29%2F%28x%2B2%29+

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Polynomials-and-rational-expressions/88199: Can someone help me please. Factor the polynomial by factoring out the negative of the GCF -24x4y3+30x2y3
1 solutions

Answer 64041 by rapaljer(4667) About Me  on 2007-07-12 15:03:55 (Show Source):
You can put this solution on YOUR website!
The GCF is the largest factor that divides into both terms in this expression-24x%5E4y%5E3%2B30x%5E2y%5E3. If variables are involved, it will be the LOWEST power of each variable. This would be 6x%5E2y%5E3.

When you take out the NEGATIVE of this common factor, it changes all the signs. What is left is this:
-6x%5E2y%5E3%284x%5E2+-+5%29

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Equations/88162: Rewrite the equation 4x – 6y = –30 as a function of x
1 solutions

Answer 64017 by rapaljer(4667) About Me  on 2007-07-12 11:42:08 (Show Source):
You can put this solution on YOUR website!
4x – 6y = –30

Get the x term isolated by adding +6y to each side:
4x = 6y-30

Divide both sides by 4. There are two ways to write this:
%284x%29%2F4+=+%286y-30%29%2F4 or %284x%29%2F4+=+%28%286y%29%2F4%29-%2830%2F4%29
x+=+%282%283y-15%29%29%2F4 or x+=+%28%283y%29%2F2%29-%2815%2F2%29
x+=+%283y-15%29%2F2
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Geometry_Word_Problems/88172: an angle is 14 degrees more than the measure of its complement. find the number of degrees in each angle
1 solutions

Answer 64015 by rapaljer(4667) About Me  on 2007-07-12 11:36:31 (Show Source):
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Let x = first angle
x+14= second angle

x+x+14 = 90
2x +14= 90
2x=76
x= 38 degrees
x+14= 52 degrees

Check: 38+52 = 90 degrees

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Geometry_Word_Problems/88176: two angles are complementary one contains 30 degrees more than the other . find both angles
1 solutions

Answer 64013 by rapaljer(4667) About Me  on 2007-07-12 11:34:11 (Show Source):
You can put this solution on YOUR website!
Let x= first angle
x+30 = second angle

x+ x+ 30= 180
2x= 150
x= 75 degrees
x+30 = 105 degrees

Check 75+105= 180

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Coordinate-system/88175: A satellite orbits the Earth on a path with equation x^2 + y^2 = 45 000 000. Another satellite, on the same plane, is currently located at (12 504, 16 050). Is the second satellite inside or outside the orbit of the first satellite? Explain.
THNAK u
1 solutions

Answer 64012 by rapaljer(4667) About Me  on 2007-07-12 11:31:54 (Show Source):
You can put this solution on YOUR website!
Assuming that the earth is located at the point (0,0), find the distance between (0.0) and the satellite at (12 504, 16 050).
Find d%5E2=+%2812504%5E2%2B+16050%5E2%29=+413952516. Since this d%5E2 is greater than the d%5E2=45000000 of the orbit of the other satellite, I would say that it is OUTSIDE the orbit of this satellite.

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Percentage-and-ratio-word-problems/88173: I had 14 Leases in June and 0 Leases for May. What is my percentage of increase for June over May?
How do I figure this?
Thank You
1 solutions

Answer 64011 by rapaljer(4667) About Me  on 2007-07-12 11:21:46 (Show Source):
You can put this solution on YOUR website!
Percent of increase is always the amount of increase divided by the original amount. In this case you have an increase of 14, but the original amount is ZERO. You can't divide by zero, so the percent of increase is "undefined" or "infinity"!!

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Geometry_Word_Problems/88170: two angles of a triangle have equal measures but the third angles measure is 36 degrees less than the sum of the other two . find the measure of each angle of the triangle
1 solutions

Answer 64010 by rapaljer(4667) About Me  on 2007-07-12 11:19:03 (Show Source):
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Let x = measure of one of the equal angles
2x-36 = third angle

x + x + 2x-36 = 180
4x - 36= 180
4x -36+36= 180+36
4x = 216
x= 54 Degrees = Equal angles
2x-36 = 72 Degrees = Third angle

Check: 54+54+72= 180 degrees

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Quadratic_Equations/88166: Can someone show me how to do this problem with step by step instructions. Thank you
The height h in feet of an object after t seconds is given by the function h=16t^2+90t+8.
How long will it take the object to hit the ground? Round your answer to the nearest thousandth.
1 solutions

Answer 64009 by rapaljer(4667) About Me  on 2007-07-12 11:14:27 (Show Source):
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Are you sure you copied this correctly? This particular equation NEVER hits the ground. Maybe you meant to say h=-16t%5E2%2B90t%2B8??

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Linear-equations/88167: Find the slope of the graph of the linear function.
f(2)=4, f(0)=6
1 solutions

Answer 64008 by rapaljer(4667) About Me  on 2007-07-12 11:11:55 (Show Source):
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f(2)=4, f(0)=6

Slope = %28RISE%29%2F%28RUN%29
RISE = 6-4=2
RUN=0-2=-2
Slope = %28RISE%29%2F%28RUN%29=2%2F-2=-1.

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Rectangles/88169: This question is from textbook Geometry:Seeing, Doing, Understanding
In a quadrilateral with equal diagonals, why can't we conclude that it is a rectangle?
1 solutions

Answer 64007 by rapaljer(4667) About Me  on 2007-07-12 11:08:52 (Show Source):
You can put this solution on YOUR website!
I apologize for my WRONG answer here!! It was pointed out to me that a trapezoid can have equal diagonals! I completely forgot about these. Diagonals of a quadrilateral being equal does NOT imply rectangularity!! I sincerely apologize for my error!!

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Polynomials-and-rational-expressions/88164: Could someone help me please. This is a trinomial not a polynomial.
Find the constant term that should be added to make the following expression a perfect square trinomial.
x^2+18x
1 solutions

Answer 64006 by rapaljer(4667) About Me  on 2007-07-12 11:04:00 (Show Source):
You can put this solution on YOUR website!
This is called "completing the square". Assuming that the coefficient of the x^2 term is 1, you take HALF of the x coefficient, and SQUARE it. In this case, take HALF of 18 (which is 9) and SQUARE (which is 81).

Now you have
x%5E2%2B18x%2B+81
%28x%2B9%29%5E2

The final answer is 81.

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Complex_Numbers/88099: Use DeMoivre's Theorem to find the indicated power of the complex number. Write the answer in rectangular form:
[1/2(cos pi/10 + i sin pi/10)]^5
1 solutions

Answer 64004 by rapaljer(4667) About Me  on 2007-07-12 09:25:17 (Show Source):
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According to DeMoive's Theorem
%281%2F2%29%28cos+%28pi%2F10%29+%2B+i+sin+%28pi%2F10%29%29%5E5
=%28%281%2F2%29%5E5%28cos+%285%2Api%2F10%29+%2B+i+sin%285%2Api%2F10%29%29%29
=%28%281%2F32%29%28cos+%28pi%2F2%29+%2B+i+sin%28pi%2F2%29%29%29

Now, cos%28pi%2F2%29=0 and sin%28pi%2F2%29=+1
=%28%281%2F32%29%28cos+%28pi%2F2%29+%2B+i+sin%28pi%2F2%29%29%29
=%28%281%2F32%29%280+%2B+i+%2A1%29%29
= i%2F32 or %281%2F32%29%2Ai

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Expressions-with-variables/88115: I need some help with this problem
Social Sience
in a town election, the winning candidate had 220 more votes than the loser. if 810 votes were cast in all, how many votes did each candidate receive?

1 solutions

Answer 63975 by rapaljer(4667) About Me  on 2007-07-12 00:39:32 (Show Source):
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Let x = votes cast for the loser
x+ 220 = votes cast for the winner
Total votes cast= 810

x + x+ 220 = 810
2x + 220 = 810
2x+220-220= 810-220
2x= 590
x= 295 votes for the loser
x+ 220 = 515 votes for the winner

Check: 295+ 515 = 810 total votes cast

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Geometry_Word_Problems/88133: find the length of the side of a square with the perimeter of 60 cm
1 solutions

Answer 63973 by rapaljer(4667) About Me  on 2007-07-12 00:35:31 (Show Source):
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Let x = side of square
4x = 60
x= 15 cm

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Polynomials-and-rational-expressions/88121: If there are 6 * 10^9 people on the Earth and there is enough freshwater
to provide each person with 8.79 * 10^5 L, how much freshwater is on the
Earth?

1 solutions

Answer 63972 by rapaljer(4667) About Me  on 2007-07-12 00:33:25 (Show Source):
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Multiply the number of people times the number of liters of water per person:
6+%2A+10%5E9+%2A8.79+%2A+10%5E5+
%286+%2A8.79%29+%2A+10%5E9+%2A+10%5E5+ When you multiply numbers like 10%5E9%2A10%5E5, you add exponents!
%2852.74%29%2A10%5E14

Now, change to scientific notation by converting 52.74 to 5.274%2A10%5E1.
%285.274+%2A10%5E1%29+%2A10%5E14
5.274%2A10%5E15+

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Geometry_Word_Problems/88134:
1 solutions

Answer 63971 by rapaljer(4667) About Me  on 2007-07-12 00:24:39 (Show Source):
You can put this solution on YOUR website!
Perimeter of a triangle is just the sum of the three sides. So, add up the sides:
x +3x +3x+2= 37
7x + 2 = 37
7x= 35
x= 5
3x = 15
3x+2 = 17

Check: 5 + 15+ 17 = 37 It checks!

See my Lesson Plan in algebra.com, or go to my own website by clicking on my tutor name "rapaljer" anywhere in algebra.com. Look for my MATH IN LIVING COLOR PAGES, then go to Basic Algebra, Chapter 1, then look for the section on Word Problems. FREE and in COLOR!! How is that!!!

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Geometry_Word_Problems/88135: =22/the circumference of a circle is 132 yds find the radius using pie 7
1 solutions

Answer 63969 by rapaljer(4667) About Me  on 2007-07-12 00:19:07 (Show Source):
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The formula for Circumference is C=+pi%2Ad+ or C=+2%2Api%2Ar. Since you want the radius, take the second equation:
C=+2%2Api%2Ar
132=+2%2A%2822%2F7%29%2Ar
132=+%2844%2F7%29%2Ar

To eliminate the fraction 44%2F7, multiply both sides by the reciprocal of the fraction which is 7%2F44 .
%287%2F44%29%2A%28132%2F1%29=%287%2F44%29%2A+%2844%2F7%29%2Ar
7%2A3+=+r

Did you notice that 44 divides into 132 exactly 3 times? That may make the calculation easier. Or just use a calculator. It comes out to an even 7*3= 21 yards.

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Geometry_Word_Problems/88136:
1 solutions

Answer 63967 by rapaljer(4667) About Me  on 2007-07-12 00:09:54 (Show Source):
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Let x = longer side (length)
x-3 = shorter side (width)

2L + 2W = P
2(x) + 2(x-3) = 54
2x+2x-6=54
4x-6= 54

Add +6 to each side:
4x-6+6=54+6
4x= 60
x=15 Length
x-3= 12 = Width

Check:
2(15) + 2(12 ) = 54
30+ 24= 54
It checks!

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Equations/88126: I know the answer is 5 and 12 but I can't get it to show as an equation (I must show my work and explann it in front of class tommorrow morning Help.
1 solutions

Answer 63963 by rapaljer(4667) About Me  on 2007-07-12 00:04:15 (Show Source):
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This is like working a problem backwards, starting from the answer and ending up with a quadratic equation. Start with
x=5 and x= 12
Write each of these as mini-equations equal to zero.
x-5=0 and x-12=0

Now, write the product of these factors equal to zero:
(x-5)*(x-12)=0

Finally, multiply it all out:
x%5E2+-+17x+%2B+60+=+0

I hope you get this in time for your presentation!!

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Polynomials-and-rational-expressions/87839: Simplify.

square root of 7 over 100
1 solutions

Answer 63941 by rapaljer(4667) About Me  on 2007-07-11 20:43:49 (Show Source):
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The answer in simplest radical form is %28sqrt%287%29%29%2F10. It's always best, unless instructed to do otherwise, to rationalize the denominator.

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test/88025: Find the slope of the line passing through the points (1, 4) and (7, 2).
1 solutions

Answer 63940 by rapaljer(4667) About Me  on 2007-07-11 20:38:32 (Show Source):
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The correct answer is -1/3. The other tutor made a small error. Sorry about that.

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Numeric_Fractions/87969: Factor the trinomial.
s2 + s + 14
1 solutions

Answer 63939 by rapaljer(4667) About Me  on 2007-07-11 20:36:06 (Show Source):
You can put this solution on YOUR website!
You asked to factor this trinomial! This trinomial CANNOT be factored! Moreover, this is NOT an equation, so you can't solve it by quadratic formula, as one of the other tutors tried to do. It is INCORRECT to solve something that is NOT an equation to begin with!!

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Square-cubic-other-roots/88030: Use Property 2 to simplify each of the following radical expressions.
square root of 10/49
The answer I got is square root of 10 over 7
1 solutions

Answer 63937 by rapaljer(4667) About Me  on 2007-07-11 20:32:48 (Show Source):
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I just want you to know that I got your answer!! Your answer is in simplest radical form, no matter what anyone else may tell you!!!

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Functions/88014: Explain the meaning of a function. Give an example.
1 solutions

Answer 63902 by rapaljer(4667) About Me  on 2007-07-11 15:42:24 (Show Source):
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A function is a set of points such that no two points have the same x coordinate. An example of a function is y=x%5E2.

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Polynomials-and-rational-expressions/88007: 4/x+4= 5/x-1 I have to solve this equation(i.e. x=4 or 6)
1 solutions

Answer 63901 by rapaljer(4667) About Me  on 2007-07-11 15:40:46 (Show Source):
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Remember that a%2Fb=c%2Fd means that ad=bc.
Likewise, 4%2F%28x%2B4%29=+5%2F%28x-1%29 means that 4%28x-1%29+=+5%28x%2B4%29+. This is easy to solve!
4%28x-1%29+=+5%28x%2B4%29+
4x-4+=+5x%2B+20

Subtract 4x from each side:
4x-4-4x+=+5x%2B20+-4x
-4+=+x%2B20

Subtract 20 from each side:
-4-20=x%2B20-20
x=-24

Check the answer by substituting the value into the original equation:
4%2F%28x%2B4%29=+5%2F%28x-1%29
4%2F%28-24%2B4%29=+5%2F%28-24-1%29
4%2F-20=+5%2F-25
-1%2F5=-1%2F5 It checks!!

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test/88013: What is the third term of a recursive sequence that follows the pattern x - 7 and has a first term x = 100?
1 solutions

Answer 63899 by rapaljer(4667) About Me  on 2007-07-11 15:34:34 (Show Source):
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If the first term is 100, the second term would be 93, and the third term would be 7 less than this which would be 86. Right???

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Functions/88008: find the function , quation of the line, that mathmatically models the data where the imput is the year (x) and the output is the cost of the war (y)
2007 and predict for 2008
2007 cost is 442 billion
1 solutions

Answer 63897 by rapaljer(4667) About Me  on 2007-07-11 15:32:59 (Show Source):
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You didn't give us enough information!

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Polynomials-and-rational-expressions/88010: 2
8t +20t-12=0 That is supposed to read 8t squared. I need to solve the equation(i.e. x=4 or 6)
1 solutions

Answer 63896 by rapaljer(4667) About Me  on 2007-07-11 15:31:10 (Show Source):
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8t%5E2+%2B20t-12=0

First factor the common factor of 4:
4%282t%5E2+%2B+5t-3%29=0+

Next, you have to factor the trinomial. By the way, this is a problem all in itself! Do you know how to factor these what I call "Advanced Trinomials"? I have a lesson on this if you are interested! Anyway, here is the factored form:
4%282t-1%29%28t%2B3%29+=+0

Now, of the factors given above, the 4 factor cannot equal zero, so it does not give you any solutions. However, the other two factors do give solutions:
2t-1=0 or t%2B3=0
2t=1
t=1%2F2 or t=-3

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Polynomials-and-rational-expressions/88009: (2y-9)(y+4)(y-5)=0 I have to solve this equation(i.e. x=4 or 6)
1 solutions

Answer 63895 by rapaljer(4667) About Me  on 2007-07-11 15:25:43 (Show Source):
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When you have a product of factors equal to zero, then one of the factors must be zero. That is,
(2y-9)(y+4)(y-5)=0
2y-9 = 0 or y+4= 0 or y-5=0
2y=9
y=9%2F2 or y=-4 or y=5

R^2 Retired from SCC