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JBarnum answered: 2042 problems
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Angles/344135: TR bisects m%3CWTG

=4x+12 and m%3CRTG

=9x-13, then find x and the measure of all three angles
1 solutions

Answer 246216 by JBarnum(2044) on 2010-09-16 17:37:19 (Show Source):

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Bisecting means that it splits the angle directly in half so the 2 new angles made have the same measure
4x%2B12=9x-13

=4x+12

=32
.

=9x-13

=32
.

=64

Angles/344132: P is the interior of 1 solutions

Answer 246210 by JBarnum(2044) on 2010-09-16 17:20:06 (Show Source):

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ok this isnt very clear where is "l" located, i get TED and inbetween angle TED is P to make PED or TEP but where is the "l" and 5+4 is 9 unless there was suppose to be an "x" variable...please write your question clearly and correctly. thanks.

test/344112: Evaluate | -10d + a | A= -1. D= -14
1 solutions

Answer 246203 by JBarnum(2044) on 2010-09-16 17:06:01 (Show Source):

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subtitute and solve
|-10(-14)+(-1)|
|140+(-1)|
|139|
highlight%28139%29

Expressions-with-variables/344115: If the body mass index is 25 or higher, then you are at a higher risk for heart disease.The Ca
1 solutions

Answer 246198 by JBarnum(2044) on 2010-09-16 16:57:49 (Show Source):

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not a question

test/344108: 5x-3 (x-4) = 6x+4
1 solutions

Answer 246197 by JBarnum(2044) on 2010-09-16 16:57:04 (Show Source):

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%285x-3%29%28x-4%29=6x%2B4

Solved by pluggable solver: SOLVE quadratic equation with variable

Quadratic equation ax%5E2%2Bbx%2Bc=0

(in our case 5x%5E2%2B-29x%2B9+=+0

) has the following solutons:

x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac

should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac

.

Discriminant d=661 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--29%2B-sqrt%28+661+%29%29%2F2%5Ca

x%5B1%5D+=+%28-%28-29%29%2Bsqrt%28+661+%29%29%2F2%5C5+=+5.47099202643649

x%5B2%5D+=+%28-%28-29%29-sqrt%28+661+%29%29%2F2%5C5+=+0.329007973563512

Quadratic expression 5x%5E2%2B-29x%2B9

can be factored:
5x%5E2%2B-29x%2B9+=+5%28x-5.47099202643649%29%2A%28x-0.329007973563512%29

Again, the answer is: 5.47099202643649, 0.329007973563512. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+5%2Ax%5E2%2B-29%2Ax%2B9+%29

test/344086: Undefined and defined

1 solutions

Answer 246177 by JBarnum(2044) on 2010-09-16 16:17:13 (Show Source):

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"In mathematics, defined and undefined are used to explain whether or not expressions have meaningful, sensible, and unambiguous values. Whether an expression has a meaningful value depends on the context of the expression. For example the value of 4 − 5 is undefined if a positive integer result is required."

please see:
http://en.wikipedia.org/wiki/Defined_and_undefined
or
http://en.wikipedia.org/wiki/Well-definition

If you want a tutor to answer a question please specify your questions.

test/344082: Your question goes here. Write clearly! We are not mind readers, so be sure to ask a question that we can understand.
1 solutions

Answer 246174 by JBarnum(2044) on 2010-09-16 16:12:39 (Show Source):

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why are you writing this here we are the tutors...waste of time. write a lesson or turorial not ask us a question.

test/344083: Your question goes here. Write clearly! We are not mind readers, so be sure to ask a question that we can understand.
1 solutions

Answer 246173 by JBarnum(2044) on 2010-09-16 16:11:49 (Show Source):

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why are u writing this here we are the tutors...waste of time. write a lesson or turorial not ask us a question.

test/344067: Hii. Working on algebra two word problems and it so frustraiting!
1)ace rent a car charges a flat fee of $15 and $0.24 a mile for their cars. Acme rent a car charges a flat fee of $29 and $0.14 a mile for their cars. Use the following model to find out after how many miles ace rent a car becomes more expensive then acme rent a car.
1 solutions

Answer 246166 by JBarnum(2044) on 2010-09-16 16:04:22 (Show Source):

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whats "the following model?" cause i dont see anything in this submission
A=ace
C=Acme
mi=mile
A=15%2B0.24mi

we want to know when A>C
A%3EC

so this means that at 141 miles Ace will cost more than Acme

to check simply plug in the number for above equations
A=48.84 at 141 miles
C=48.74 at 141 miles

Angles/344064: angle A is 18 more than five times its complement angle B
1 solutions

Answer 246157 by JBarnum(2044) on 2010-09-16 15:44:45 (Show Source):

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Complementary angles add up to 90

A=18+5B
A+B=90
18%2B5B%2BB=90
18%2B6B=90
6B=72
B=12

A=18%2B5%2812%29
A=18%2B60
A=78

Check
A%2BB=90
78%2B12=90
90=90
Correct

Angles/344061: angle A is 21 less than twice as large as its supplement angle B
1 solutions

Answer 246152 by JBarnum(2044) on 2010-09-16 15:37:40 (Show Source):

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supplement angles add up to 180
A+B=180
A=2B-21 "A is 21 less than twice as large as its supplement angle B"

i dont know if ur looking for just the expression or trying to solve for each angle?

%282B-21%29%2BB=180
3B=201
B=67

A=2B-21
A=2%2867%29-21
A=134-21
A=113

Check
A%2BB=180
113%2B67=180
180=180
Correct

Expressions-with-variables/344058: don planted t fewer trees than franciso. francisco planted52 tress. write an expression that shows how many pennies qilson has now

1 solutions

Answer 246142 by JBarnum(2044) on 2010-09-16 15:17:37 (Show Source):

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lol what are you sure you didnt write 2 diffrent questions together?
D=don
F=francisco
D=F-t
F=52
D=52-t

But who is qilson and what pennies?

Travel_Word_Problems/343464: A bicyclist travels at 10 miles per hour. How long will it take the bicyclist to travel 30 miles?
1 solutions

Answer 245780 by JBarnum(2044) on 2010-09-15 13:37:20 (Show Source):

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highlight%283%29

hours

10 mi / 1 hr
total 30 miles
10%2F1=30%2Fx
1%2A30=10x
30=10x
30%2F10=x
3=x

Expressions-with-variables/335195: C=5/9(s-32)
Solve for S
1 solutions

Answer 240214 by JBarnum(2044) on 2010-08-26 07:28:42 (Show Source):

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multiply by 9/5
%289%2F5%29C=%28s-32%29

add 32

Equations/331578: Geoff has a square bedroom. He measures one of the walls and finds it is 20 ft long. How many square feet are in his bedroom?
1 solutions

Answer 237661 by JBarnum(2044) on 2010-08-13 11:41:22 (Show Source):

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square room means all sides are the same
if one side is 20 then all sides are 20
to find Area
use area formula
A=LW
if L=20

and

then

Polynomials-and-rational-expressions/331561: Multiplty. (3√5-9√7)(2√5+6√7)

1 solutions

Answer 237652 by JBarnum(2044) on 2010-08-13 10:33:19 (Show Source):

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%283sqrt%285%29-9sqrt%287%29%29%282sqrt%285%29%2B6sqrt%287%29%29

foil

multiply

%286sqrt%2825%29%29%2B%2818sqrt%2835%29%29%2B%28-18sqrt%2835%29%29-%2854sqrt%2849%29%29 factor and cancel

%286%2A5%29%2Bcross%2818sqrt%2835%29%29%2Bcross%28-18sqrt%2835%29%29-%2854%2A7%29%29

%286%2A5%29-%2854%2A7%29 multiply

%2830%29-%28378%29 subtract

highlight%28-348%29

Polynomials-and-rational-expressions/331560: solve. (x+13)(x-10)(x+8)>0

1 solutions

Answer 237649 by JBarnum(2044) on 2010-08-13 10:19:21 (Show Source):

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x+13>0 , x-10>0 , x-8>0
x>-13 ,x>10 ,x>8

Radicals/331564: Simplify by taking roots of the numerator and the denominator. Assume that all expressions under radicals represent positive numbers. ∛125x^14/y^3
1 solutions

Answer 237648 by JBarnum(2044) on 2010-08-13 10:16:15 (Show Source):

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again, please write the correct equation...this can mean different possibilities
i will solve as u have imputted it( 3sqrt%28x%29

means 3rd root of x)
3sqrt%28125x%5E14%29%2Fy%5E3

3sqrt%285%5E3%28x%5E4%29%5E3x%5E2%29%2Fy%5E3

Polynomials-and-rational-expressions/331557: Perform the indicated operations and simplify. z-4/z-5-z+1/z+5+z-15/z^2-25

1 solutions

Answer 237645 by JBarnum(2044) on 2010-08-13 10:00:17 (Show Source):

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please make sure u write the equation correctly since im having to guess what it looks like
according to how you inputted the equation this is what it would look like
z-%284%2Fz%29-5-z%2B%281%2Fz%29%2B5%2Bz%28-15%2Fz%5E2%29-25

z-%284%2Fz%29-5-z%2B%281%2Fz%29%2B5%2Bz%28-15%2Fz%5E2%29-25

however im pretty sure u meant this:
factor

common denom

add fractions

foil

%28%28z%5E2%2Bz-20%29-%28z%5E2-4z-5%29%2B%28z-15%29%29%2F%28%28z-5%29%28z%2B5%29%29 add like terms

%28z%5E2%2Bz-20-z%5E2%2B4z%2B5%2Bz-15%29%2F%28%28z-5%29%28z%2B5%29%29 add like terms

%286z-30%29%2F%28%28z-5%29%28z%2B5%29%29 factor

6%28z-5%29%2F%28%28z-5%29%28z%2B5%29%29 cancelation

6cross%28z-5%29%2F%28cross%28z-5%29%28z%2B5%29%29

highlight%286%2F%28z%2B5%29%29

Miscellaneous_Word_Problems/331551: Suppose we have a pendulum that is “y” feet long. Our pendulum makes one complete swing in “t” seconds. Assume “y” and “t” are related by the formula y = .9 t2. If the pendulum is less than 4 feet long, what is the range of values for “t”?

I really need help with this one I don't even know where to start.
1 solutions

Answer 237634 by JBarnum(2044) on 2010-08-13 09:25:40 (Show Source):

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from the looks of it u have an equation
y=.9t%5E2

and you have what y =
y%3C4

so:

divide by .9
4.4444%3Et%5E2

t=2.1082 or -2.1082 since we cant go back in time negative wouldnt be an answer
so the time takes less than 2.1082 seconds
range from [0 , 2.1082]

Complex_Numbers/331548: 4x-8(x+2)=-4x-5
1 solutions

Answer 237632 by JBarnum(2044) on 2010-08-13 09:17:23 (Show Source):

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4x-8%28x%2B2%29=-4x-5

no solution

Polynomials-and-rational-expressions/331553: find the greatest common factor for the group of terms. -66a^4,11a^5

1 solutions

Answer 237631 by JBarnum(2044) on 2010-08-13 09:13:48 (Show Source):

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11 goes into -66 and 11
a^4 goes into a^4 and a^5
highlight%2811a%5E4%29

factored looks like this
11a%5E4%28-6%29

Polynomials-and-rational-expressions/331554: find the greatest common factor for the group of terms. -66a^4,11a^5

1 solutions

Answer 237630 by JBarnum(2044) on 2010-08-13 09:12:57 (Show Source):

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11 goes into -66 and 11
a^4 goes into a^4 and a^5
highlight%2811a%5E4%29

factored looks like this
11a%5E4%28-6%29

Radicals/331552: subtract. simplify by collecting like radical terms if possible. 7√32-7√2

1 solutions

Answer 237628 by JBarnum(2044) on 2010-08-13 09:10:02 (Show Source):

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7sqrt%2832%29-7sqrt%282%29

Linear-equations/331547: What is the y-intercept of the line parallel to 2y = 3x + 8 and passing through
(4, 16)?
1 solutions

Answer 237626 by JBarnum(2044) on 2010-08-13 08:55:10 (Show Source):

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y=%283%2F2%29x%2B4

keep the slope since its //
substitute x and y, and replace 4 with b
%2816%29=%283%2F2%29%284%29%2Bb

solve for b
%2816%29=%283%29%282%29%2Bb

this is you y-intercept

Age_Word_Problems/331545: find their present age
x+y=42-jed
y+z=59-Johnny
x+z=53 joseph
1 solutions

Answer 237625 by JBarnum(2044) on 2010-08-13 08:45:46 (Show Source):

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?u have 6 variables and only 3 equations...u will not get actual ages, please submit the question u derived these equations from because im possitive these equations are incorrect.
this is what i see:
x%2By=42-d

d=jed current age
y%2Bz=59-n

n=johnny current age
x%2Bz=53-h

h=joseph current age

percentage/331521: These are my questions that need help with:
1.Which of the following is equivalent to (10-4i )/(1-i)?
2.Which of the following correctly represents 0.14 as a fraction.
3.What is the derivative of g(x) = (x2 + 1)(x3 + 3) with respect to x?
4.A set of test scores has a mean of 73% and a standard deviation of 8. Approximately what percentage of students scored between 65% and 81% on the test?
5.What is the probability of drawing a red face card (i.e. a red jack, queen, or king) from a standard deck of 52 cards?
6.Which of the following angles is complementary to & #952; = 2& #960;/9 radians?
7.In a circle is a tangent at A. If the area of circle O is 16π and BO = 1, what is the circumference of P?

1 solutions

Answer 237620 by JBarnum(2044) on 2010-08-13 08:37:28 (Show Source):

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I dont see how these are related to percents?

1.Which of the following is equivalent to (10-4i )/(1-i)?
uh where are the selections??

2.Which of the following correctly represents 0.14 as a fraction.
Where are the selections? 7/50? 14/100?

3.What is the derivative of g(x) = (x^2 + 1)(x^3 + 3) with respect to x?
sry im not this far in calculus to help you please try seperate question in calculus section since this is not a percent question.

4.A set of test scores has a mean of 73% and a standard deviation of 8. Approximately what percentage of students scored between 65% and 81% on the test? this is a percent question hoewver still this calculus in deviations is above my knowledge.

5.What is the probability of drawing a red face card (i.e. a red jack, queen, or king) from a standard deck of 52 cards?
but anyway 2 red jacks 2 red queens and 2 red kings so 6 of 52 3/26 chance or .1154 is my guess
this is probability question not percent, you should really ask these questions in different categories as tutors can do some problems where others cant. im great in algebra but not probability, granted this is algebra.com. gl with these questions.

6.Which of the following angles is complementary to & #952; = 2& #960;/9 radians?
please write the correct symbol if you want it to be answered. and still not a percentage.

7.In a circle is a tangent at A. If the area of circle O is 16& # 960; and BO = 1, what is the circumference of P?
& #960?? what? please type the symbols in as pasting does this i dont know what that is.
Again not a percentage, please post in correct category as that is why we have categories. for people to view questions like these and to have the correct tutors be able to solve these questions, putting a bunch of random questions in one post will get you this type of responce, or no responce at all.

Square-cubic-other-roots/331463: the square of m minus the cube of n is sixteen
1 solutions

Answer 237615 by JBarnum(2044) on 2010-08-13 07:35:53 (Show Source):

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m%5E2-n%5E3=16

what are you trying to solve?

Age_Word_Problems/331473:
1 solutions

Answer 237614 by JBarnum(2044) on 2010-08-13 07:34:07 (Show Source):

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??

Square-cubic-other-roots/331484: the slope of a line that is perpendicular to (2,4) (-1,0) is
1 solutions

Answer 237612 by JBarnum(2044) on 2010-08-13 07:22:39 (Show Source):

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find the slope of this line then the reciprical of that slope is the slope ur looking for.
0-4/-1-2
-4/-3
4/3
reciprical is highlight%283%2F4%29

absolute-value/331494: I need to understand how this problem is solved? can you help? here it is
absolute value and decimals____|-14.1+6.9|+8
1 solutions

Answer 237611 by JBarnum(2044) on 2010-08-13 07:14:27 (Show Source):

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absolute value simply means whatever is inside will become positive no matter what
so inside the || add the numbers
|-7.2|+8 us the absolute value property
7.2+8 add the numbers
highlight%2815.2%29

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Recent problems solved by 'JBarnum'