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answered: 49 problems
Jump to solutions: 0..29 , 30..59Polynomials-and-rational-expressions/241500: I NEED HELP WITH TRINOMALS
2 solutions
Answer 176871 by College Student(217)   on 2009-11-21 20:57:54 (Show Source):
You can put this solution on YOUR website!Hello!
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If you are looking for long explanations, the following web page is very good and it shows examples. http://www.themathpage.com/Alg/factoring-trinomials.htm
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However, if you just need help with some problems, please post them.
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Thank you!
Answer 176870 by unlockmath(121)  on 2009-11-21 20:55:36 (Show Source):
You can put this solution on YOUR website!Hello,
This is quite a loaded question since many many pages can be written about trinomials.
To begin, the word means: tri- (which is 3) and -nomial (is name or term). So it's 3 names or terms.
Here's an example of a trinomial 3x^2 + 2x + 17 this can also be called a polynomial. (Poly means several)
RJ Toftness
www.math-unlock.com
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Polynomials-and-rational-expressions/241484: Factor the trinomial, or state that the trinomial is prime.
x²-3x-18
x²-3x-18=
Type P if the polynomial is prime.
1 solutions
Answer 176866 by stanbon(26297)  on 2009-11-21 20:04:50 (Show Source):
You can put this solution on YOUR website!Factor the trinomial, or state that the trinomial is prime.
x²-3x-18
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Think of two numbers whose product is -18 and whose sum is -3.
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The numbers are -6 and 3
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Rewrite the problem making this substitution:
x^2 - 6x + 3x -18
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Factor the 1st two and the last two terms separately:
x(x-6) + 3(x-6)
Factor again to get the solution:
(x-6)(x+3)
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Cheers,
stan H.
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Evaluation_Word_Problems/241482: The difference between six times a number and 9 is equal to five times the sum of the number and 2.Find the number.Ok my answer was 19 but i wasn't sure if it was correct.So this is how i worked it out:6x-9=5(x+2),6x=5x+19,x=19
1 solutions
Answer 176865 by stanbon(26297) on 2009-11-21 20:00:18 (Show Source):
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Word_Problems_With_Coins/241479: Is it possible to spend $30 for 100 stamps consisting of 20-cent stamps and 33-cent stamps?
2 solutions
Answer 176864 by stanbon(26297) on 2009-11-21 19:58:02 (Show Source):
You can put this solution on YOUR website!Is it possible to spend $30 for 100 stamps consisting of 20-cent stamps and 33-cent stamps?
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Equations:
Quantity: t + r = 100
Value::: 20t+33r = 3000
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Multiply thru the Quatity Eq. by 20 to get:
20t + 20r = 2000
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Subtract that from the Value Eq. to get:
13r = 1000
r = 76.92
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Since r is the number of thirty cent stamps and is not
an integer the combination does not work.
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Cheers,
Stan H.
Answer 176863 by checkley77(7072) on 2009-11-21 19:53:44 (Show Source):
You can put this solution on YOUR website!x+y=100 or x=100-y
.20x+.33y=30
.20(100-y)+.33y=30
20-.20y+.33y=30
.13y=30-20
.13y=10
y=10/.13
y=76.9 33 cent stamps.
Ans. is NO.
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logarithm/241480: please help me solve:
log base 5 (x^2+x+4)=2
1 solutions
Answer 176862 by stanbon(26297) on 2009-11-21 19:52:13 (Show Source):
You can put this solution on YOUR website!log base 5 (x^2+x+4)=2
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x^2+x+4 = 5^2
x^2 + x -21 = 0
x = [-1 +- sqrt(1 -4*-21)]/2
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x = [-1 +sqrt(85)]/2 or x = [-1-sqrt(85)]/2
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Cheers,
Stan H.
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logarithm/241478: Solve for x: log(x^6)=(log x)^2
Note, there are 2 solutions, A and B where A
A=?
B=?
Any help would be greatly appreciated. I'm really stuck on this one. Thanks.
2 solutions
Answer 176861 by stanbon(26297) on 2009-11-21 19:45:31 (Show Source):
You can put this solution on YOUR website!Solve for x: log(x^6)=(log x)^2
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6log(x) = (log(x))^2
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Rewrite:
(log(x))^2 - 6log(x) = 0
Factor:
[log(x)][log(x)-6] = 0
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log(x) = 0 or log(x) = 6
x = 10^0 = 1 or x = 10^6 = 1,000,000
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Cheers,
Stan H.
Answer 176858 by Alan3354(6097)  on 2009-11-21 19:38:22 (Show Source):
You can put this solution on YOUR website!log(x^6)=(log x)^2
(log x)^2 = 6log(x)
(log x)^2 - 6log(x) = 0
log(x) * [log(x) - 6] = 0
log(x) = 0 Ignore this one
log(x) = 6
x = 10^6 = 1,000,000
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Pythagorean-theorem/241321: the sides of a triangle are 8, 15 and 17 units. if each side is doubled, by how many square units will the area of the triangle increase?
1 solutions
Answer 176860 by checkley77(7072) on 2009-11-21 19:45:02 (Show Source):
You can put this solution on YOUR website!If this is a right triangle then:
area=bh/2
area=15*8/2
area=60 square units.
area=30*16/2
area=240 square units.
The area has increased by 240-60=180 square units or a 4 fold increase.
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logarithm/241462: 6e^(2x)-16e^x=6
solve for x. please explain
2 solutions
Answer 176856 by stanbon(26297) on 2009-11-21 19:35:22 (Show Source):
You can put this solution on YOUR website!6e^(2x)-16e^x=6
solve for x. please explain
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This is a quadratic equation with e^x as it's variable:
Rewrite:
6(e^x)^2 - 16(e^x) - 6 = 0
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Let m = e^x
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6m^2 - 16m - 6 = 0
3m^2 - 8m - 3 = 0
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3m^2 -9m+m - 3 = 0
3m(m-3)+(m-3) = 0
(m-3)(3m+1) = 0
m = 3 or m = -1/3
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Substitute to solve for "x":
e^x = 3
x = ln(3) = 1.098612...
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e^x = (-1/3)
No solution because no value of e is negative.
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Cheers,
Stan H.
Answer 176854 by Alan3354(6097) on 2009-11-21 19:30:49 (Show Source):
You can put this solution on YOUR website!6e^(2x)-16e^x=6
3e^2x - 8e^x - 3 = 0
It's a quadratic in e^x. You can sub y for e^x if it makes it clearer.
--> y^2 - 8y - 3 = 0
I'll just do it with e^x
(3e^x + 1)*(e^x - 3) = 0
e^x = 3
x = ln(3)
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e^x = -1/3 Ignore this one, no exponent will give a negative (in real numbers)
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Linear_Equations_And_Systems_Word_Problems/241472: Find an equation of variation if the following conditions exist.
Suppose that y varies directly as z and y = 43 when z = 387.
1 solutions
Answer 176853 by stanbon(26297) on 2009-11-21 19:22:00 (Show Source):
You can put this solution on YOUR website!Find an equation of variation if the following conditions exist.
Suppose that y varies directly as z and y = 43 when z = 387.
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y = kz
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43 = k*387
k = 43/387
k = 1/9
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Equation:
y = (1/9)/z
y = 1/(9z)
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Cheers,
Stan H.
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