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p(x)=x^3-x^2-9x+9
it says write p(x) as a product of linear factor so what should do?
thank you 1 solutions
Answer 429257 by nerdybill(7003) on 2012-12-24 07:33:34 (Show Source):
You can put this solution on YOUR website!They basically are asking you to factor the polynomial. "Linear factors" mean they want the factors all with degree of 1.
.
p(x)=x^3-x^2-9x+9
group terms:
p(x)=(x^3-x^2)-(9x-9)
p(x)=x^2(x-1)-9(x-1)
p(x)=(x-1)(x^2-9)
p(x)=(x-1)(x^2-3^2)
p(x)=(x-1)(x-3)(x+3)
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Miscellaneous_Word_Problems/696009: What am I supposed to do if a question is like this. A school bus with capacity for 42 passengers. How many school buses are needed to transport a total of 180
passengers on a trip to the state legislature? 1 solutions
Answer 428752 by nerdybill(7003) on 2012-12-19 19:25:26 (Show Source):
You can put this solution on YOUR website!What am I supposed to do if a question is like this. A school bus with capacity for 42 passengers. How many school buses are needed to transport a total of 180
passengers on a trip to the state legislature?
.
Just divide:
180/42 = 4.29
the math says you need 4.29 buses
Since, you can't have a "partial" bus the answer is
you will need 5 buses
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logarithm/696027: How do we solve a problem that looks like this:
Log base 3 10= 2.1
Log base 3 11= 2.2
Log base 3 8= 1.9
Find Log base 3 330
Log base 3 330=? 1 solutions
Answer 428751 by nerdybill(7003) on 2012-12-19 19:19:35 (Show Source):
You can put this solution on YOUR website!How do we solve a problem that looks like this:
Log base 3 10= 2.1
Log base 3 11= 2.2
Log base 3 8= 1.9
Find Log base 3 330
Log base 3 330=?
.
Log base 3 330
Log base 3 33*10
Log base 3 3*11*10
Log base 3(3) + Log base 3(11) + Log base 3(10)
Log base 3(3^1) + Log base 3(11) + Log base 3(10)
1 + Log base 3(11) + Log base 3(10)
1 + 2.2 + Log base 3(10)
1 + 2.2 + 2.1
3.2 + 2.1
5.3
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Word_Problems_With_Coins/695858: A jar contains quarters and dimes whose value totals $4.40. It has three times as many dimes as quarters. How many dimes is in the jar. 1 solutions
Answer 428675 by nerdybill(7003) on 2012-12-19 09:06:55 (Show Source):
You can put this solution on YOUR website! A jar contains quarters and dimes whose value totals $4.40. It has three times as many dimes as quarters. How many dimes is in the jar.
.
Let d = number of dimes
then
d/3 = number of quarters
.
.10d + .25(d/3) = 4.40
.30d + .25d = 13.20
.55d = 13.20
d = 13.20/.55
d = 24 (number of dimes)
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Age_Word_Problems/694755: How can I translate this word problem into an equation? Jim is 5 years older than Joe. If the sum of their ages is 55, how old are they? 1 solutions
Answer 428176 by nerdybill(7003) on 2012-12-16 11:13:48 (Show Source):
You can put this solution on YOUR website!How can I translate this word problem into an equation? Jim is 5 years older than Joe. If the sum of their ages is 55, how old are they?
.
Let x = age of Joe
then
x+5 = age of Jim
.
x + x+5 = 55
2x + 5 = 55
2x = 50
x = 25 years old (Joe)
.
Jim:
x+5 = 25+5 = 30 years old
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Functions/694714: Let f(x)=x^2 +3x+9 and g(x)=(2x+3)/(x-2) Find f(-1)-g(0) 1 solutions
Answer 428139 by nerdybill(7003) on 2012-12-16 08:32:40 (Show Source):
You can put this solution on YOUR website! Let f(x)=x^2 +3x+9 and g(x)=(2x+3)/(x-2) Find f(-1)-g(0)
.
first, find f(1):
f(x)=x^2 +3x+9
f(1)=(1)^2 +3(1)+9
f(1)=1+3+9
f(1)=13
.
then, find g(0):
g(x)=(2x+3)/(x-2)
g(x)=(2(0)+3)/(0-2)
g(x)=(3)/(-2)
g(x)= -3/2
.
finally:
f(-1)-g(0)
13-(-3/2)
13 + 3/2
26/2 + 3/2
(26+3)/2
29/2 (answer)
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Quadratic_Equations/694657: Bob throws a ball vertically upward from the top of the cliff, the height of the ball above the base of the cliff is approximated by the model h = 65 + 10t- 5t ^2 where h is the height in metres and t is the time in seconds.
a) How high is the cliff?
b) How long does it take the ball to reach a height of 50 metres above the cliff?
c) After how many seconds does the ball hit the ground?
can you please help me out? I really don't understand can you go step by step. Thanks in advance :) 1 solutions
Answer 428123 by nerdybill(7003) on 2012-12-15 23:15:00 (Show Source):
You can put this solution on YOUR website!Bob throws a ball vertically upward from the top of the cliff, the height of the ball above the base of the cliff is approximated by the model h = 65 + 10t- 5t ^2 where h is the height in metres and t is the time in seconds.
a) How high is the cliff?
h = 65 + 10t- 5t ^2
set t to zero to find height of cliff:
h = 65 + 10(0)- 5(0)^2
h = 65 metres
.
b) How long does it take the ball to reach a height of 50 metres above the cliff?
set h to 50 and solve for t
h = 65 + 10t- 5t ^2
50 = 65 + 10t- 5t^2
0 = 15 + 10t- 5t^2
0 = -5t^2+10t+15
0 = 5t^2-10t-15
0 = t^2-2t-3
0 = (t+1)(t-3)
t = {-1, 3}
throw out the negative solution leaving:
t = 3 seconds
.
c) After how many seconds does the ball hit the ground?
set h to 0 and solve for t:
h = 65 + 10t- 5t ^2
0 = 65 + 10t- 5t^2
0 = -5t^2+10t+65
0 = 5t^2-10t-65
0 = t^2-2t-13
solve using the "quadratic equation" to get
t = {4.74, -2.74}
throw out the negative solution leaving:
t = 4.74 seconds
.
Details of quadratic equation follows:
| Solved by pluggable solver: SOLVE quadratic equation with variable |
Quadratic equation (in our case ) has the following solutons:

For these solutions to exist, the discriminant should not be a negative number.
First, we need to compute the discriminant : .
Discriminant d=56 is greater than zero. That means that there are two solutions: .


Quadratic expression can be factored:

Again, the answer is: 4.74165738677394, -2.74165738677394.
Here's your graph:
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percentage/694507: A man salary is 1850 dollars per month.Out of this 20 percent goes to his rent,690 dollars goes to foodand 940 dollars on other expenses.What percentage has he over spent? 1 solutions
Answer 427979 by nerdybill(7003) on 2012-12-15 10:05:04 (Show Source):
You can put this solution on YOUR website! A man salary is 1850 dollars per month.Out of this 20 percent goes to his rent,690 dollars goes to foodand 940 dollars on other expenses.What percentage has he over spent?
.
Total expenditure:
.20(1850) + 690 + 940
370 + 690 + 940
1060 + 940
2000
.
amount overspent:
2000-1850 = 150
.
percentage over spent:
150/1850 * 100
0.08 * 100
8%
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logarithm/694297: Solve this application using logarithms. Refer to the examples above.
How much principal, to the nearest dollar, should you invest at 4% in order to have $3,000 for a vacation to Europe in 3 years? 1 solutions
Answer 427823 by nerdybill(7003) on 2012-12-14 09:40:36 (Show Source):
You can put this solution on YOUR website!Solve this application using logarithms. Refer to the examples above.
How much principal, to the nearest dollar, should you invest at 4% in order to have $3,000 for a vacation to Europe in 3 years?
.
Assuming simple interest then:
a = pe^(rt)
3000 = pe^(.04*3)
3000 = pe^(.12)
3000/e^(.12) = p
2660.76 = p
nearest dollar:
$2661 = p
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Rate-of-work-word-problems/694276: My son can clean the attic in 4 hours and I can do it in 2 hours. How long would it take if we worked together. 1 solutions
Answer 427810 by nerdybill(7003) on 2012-12-14 08:14:33 (Show Source):
You can put this solution on YOUR website! My son can clean the attic in 4 hours and I can do it in 2 hours. How long would it take if we worked together.
.
Let x = time (hours) for both
then
x(1/4 + 1/2) = 1
x(1/4 + 2/4) = 1
x(3/4) = 1
x(3) = 4
x = 4/3 hours
or
x = 1 hour and 20 minutes
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Angles/693887: The difference between the measure of an angle and it's suplementary is 36 find the measure of the two angles 1 solutions
Answer 427614 by nerdybill(7003) on 2012-12-13 11:44:52 (Show Source):
You can put this solution on YOUR website! The difference between the measure of an angle and it's suplementary is 36 find the measure of the two angles
.
Let x = measure of angle
then
180-x = supplement of angle
.
x - (180-x) = 36
x - 180+x = 36
2x - 180 = 36
2x = 216
x = 108 degrees
.
supplement:
180-x = 180-108 = 72 degrees
.
measure of the two angles: 108 and 72 degrees
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Numbers_Word_Problems/693885: if 8 is added to twice a number and this sum is multiplied by 4 the result is the same as if the number is multiplied by 4 and 8 is added to the product 1 solutions
Answer 427611 by nerdybill(7003) on 2012-12-13 11:21:45 (Show Source):
You can put this solution on YOUR website! if 8 is added to twice a number and this sum is multiplied by 4 the result is the same as if the number is multiplied by 4 and 8 is added to the product
.
Let n = the number
then
4(2n+8) = 4n+8
8n+32 = 4n+8
4n+32 = 8
4n = 24
n = 6
.
The number is 6
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test/692675: Completing the square 2x^2+7x-4 1 solutions
Answer 427066 by nerdybill(7003) on 2012-12-10 23:26:19 (Show Source):
You can put this solution on YOUR website!Completing the square
2x^2+7x-4
group x terms:
(2x^2+7x)-4
factor out the 2:
2(x^2+7/2x) - 4
2(x^2+7/2x+49/4) - 4 - (2)(49/4)
2(x^2+7/2x+49/4) - 4 - (49/2)
2(x^2+7/2x+49/4) - 8/2- (49/2)
2(x^2+7/2x+49/4) - 57/2
2(x+7/2)^2 - 57/2
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Surface-area/691752: A rectangular room is 20 feet long and 10 feet wide. If you paint a red rectangle on the floor that is 8 feet long and 3 feet wide, what is the area of the floor in the room that will NOT be red? please help!
1 solutions
Answer 426839 by nerdybill(7003) on 2012-12-09 12:32:59 (Show Source):
You can put this solution on YOUR website!A rectangular room is 20 feet long and 10 feet wide. If you paint a red rectangle on the floor that is 8 feet long and 3 feet wide, what is the area of the floor in the room that will NOT be red? please help!
"area of room" - "red area"
(20*10) - (8*3)
(200) - (24)
176 square feet
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Money_Word_Problems/691679: how long would it take to double an investment of 1000 at 9 percent compounded quarterly? 1 solutions
Answer 426815 by nerdybill(7003) on 2012-12-09 09:22:39 (Show Source):
You can put this solution on YOUR website! how long would it take to double an investment of 1000 at 9 percent compounded quarterly?
.
Use:
A = P(1+i/n)^(nt)
where
A is amount after time t (2P)
P is the principal (P)
i is the interest per year (.09)
n is the times compounded during the year (4)
t is number of years (what we're looking for)
.
A = P(1+i/n)^(t/n)
2P = P(1+.09/4)^(4t)
2 = (1+.09/4)^(4t)
2 = (1.0225)^(4t)
 = 4t
 = t
7.79 years = t
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Miscellaneous_Word_Problems/691642: The measure of an angle is 5 times the measure of its supplement. Find the measures of the two angles 1 solutions
Answer 426793 by nerdybill(7003) on 2012-12-09 01:54:17 (Show Source):
You can put this solution on YOUR website! The measure of an angle is 5 times the measure of its supplement. Find the measures of the two angles
.
Let x = measure of angle
then
180-x = supplement of angle
.
x = 5(180-x)
x = 900-5x
6x = 900
x = 150 degrees (measure of angle)
.
supplement:
180-x = 180-150 = 30 degrees
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Quadratic-relations-and-conic-sections/691391: Write an equation for the parabola with the vertex (1,3) that passes through (-2,-15).
I have tried to figure out how to do y=A(x-h)^2, but cannot figure out how to apply it to the problem.
Sorry if topic is wrong, I can't click on the right one. 1 solutions
Answer 426677 by nerdybill(7003) on 2012-12-08 13:42:40 (Show Source):
You can put this solution on YOUR website!Write an equation for the parabola with the vertex (1,3) that passes through (-2,-15)
.
Vertex form of a parabola is
y = a(x-h)^2 + k
where
(h,k) is the vertex
.
Since the problem gives you the vertex we can plug it in:
y = a(x-1)^2 + 3
Now, we plug in the given point and solve for a:
-15 = a(-2-1)^2 + 3
-15 = a(-3)^2 + 3
-15 = a(9) + 3
-18 = a(9)
-2 = a
.
So, our equation is now:
y = -2(x-1)^2 + 3
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Volume/691412: Here is the question:
The dimensions of a brick, in inches, are 2 by 4 by 8. How many such bricks are needed to have a total volume of exactly 1 cubic foot?
I know that to find volume you multiply 2x4x8. So I did that and got 64, but I'm not sure what to do from there. Hope you can help! 1 solutions
Answer 426676 by nerdybill(7003) on 2012-12-08 13:38:06 (Show Source):
You can put this solution on YOUR website!The dimensions of a brick, in inches, are 2 by 4 by 8. How many such bricks are needed to have a total volume of exactly 1 cubic foot?
Since they give you the dimensions of the brick in INCHES -- we begin by converting 1 cubic foot into cubic inches:
12*12*12 = 1728 cubic inches
.
You already found that the volume of a brick is 64 cubic inches
.
to find how many bricks are needed to make 1 cubic foot:
1728/64 = 27 bricks
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logarithm/691405: If log(base 3)(5) = x, find log(base 3) (25/27) in terms of x 1 solutions
Answer 426674 by nerdybill(7003) on 2012-12-08 13:34:38 (Show Source):
You can put this solution on YOUR website!If log(base 3)(5) = x, find log(base 3) (25/27) in terms of x
.
log(base 3)(25/27)
log(base 3)(25) - log(base 3)(27)
log(base 3)(25) - log(base 3)(3^3)
log(base 3)(25) - 3
log(base 3)(5*5) - 3
log(base 3)(5)+log(base 3)(5) - 3
x+x - 3
2x-3
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logarithm/691401:  1 solutions
Answer 426672 by nerdybill(7003) on 2012-12-08 13:28:10 (Show Source):
You can put this solution on YOUR website!2log(base9)x = 1/2 + log(base9)(5x + 18)
log(base9)x^2 = 1/2 + log(base9)(5x + 18)
log(base9)x^2 - log(base9)(5x + 18) = 1/2
log(base9)x^2/(5x + 18) = 1/2
x^2/(5x + 18) = 9^(1/2)
x^2/(5x + 18) = 3
x^2 = 3(5x + 18)
x^2 = 15x + 46
x^2-15X = 46
x^2-15X-46 = 0
Applying the "quadratic formula" yields:
x = {17.61, -2.61}
throw out the negative solution (extraneous) leaving:
x = 17.61
.
details of quadratic follows:
| Solved by pluggable solver: SOLVE quadratic equation with variable |
Quadratic equation (in our case ) has the following solutons:

For these solutions to exist, the discriminant should not be a negative number.
First, we need to compute the discriminant : .
Discriminant d=409 is greater than zero. That means that there are two solutions: .


Quadratic expression can be factored:

Again, the answer is: 17.6118742080783, -2.61187420807834.
Here's your graph:
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