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Graphs/345691: find the slope for a line that passes through the points (-1,6) and (4,10).
1 solutions

Answer 247463 by Fombitz(13828) About Me  on 2010-09-21 09:51:54 (Show Source):
You can put this solution on YOUR website!
m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29
m=%2810-6%29%2F%284-%28-1%29%29
m=%2810-6%29%2F%284%2B1%29
Complete the calculation for the final answer.


Distributive-associative-commutative-properties/345697: 2(5x-1)=3(x+11)
1 solutions

Answer 247462 by Fombitz(13828) About Me  on 2010-09-21 09:49:26 (Show Source):
You can put this solution on YOUR website!
2%285x-1%29=3%28x%2B11%29
10x-2=3x%2B33
7x=35
highlight%28x=5%29
.
.
.
Verify,
2%285x-1%29=3%28x%2B11%29
2%285%285%29-1%29=3%285%2B11%29
2%2825-1%29=3%2816%29
2%2824%29=48
48=48
True, good solution.


Miscellaneous_Word_Problems/345704: please help me out? The doctor wants 350mg of compazine(im). In the cabinet i have 175mg/ml. What is the correct amount to give to the patient?
Could you please show me how you come up with the answer? Thank you
1 solutions

Answer 247460 by Fombitz(13828) About Me  on 2010-09-21 09:47:44 (Show Source):
You can put this solution on YOUR website!
He wants to give 350 mg.
He has 175 mg/ml.
Find the number of ml to give the patient.
N=350%2F175=2ml
.
.
.
2 ml of the solution contains 350 mg of compazine.


Matrices-and-determiminant/345687: determine the equation of a line passing through the points (1,6) and (-3,-10) using matrix equation.
1 solutions

Answer 247459 by Fombitz(13828) About Me  on 2010-09-21 09:46:15 (Show Source):
You can put this solution on YOUR website!
Which matrix equation?
Typically you just calculate the slope and use the slope-intercept form or the point-slope form of a line.


Parallelograms/345707: Find the area of the triangle with vertices

A(-4,-8),

B(-4,0), and

C(4,-6).
1 solutions

Answer 247458 by Fombitz(13828) About Me  on 2010-09-21 09:44:17 (Show Source):


Mixture_Word_Problems/345769: How many gallons of a 2% salt solution must be mixed with 20 gallons of a 7% solution to obtain a 4% solution?
1 solutions

Answer 247456 by Fombitz(13828) About Me  on 2010-09-21 09:40:32 (Show Source):
You can put this solution on YOUR website!
Let A be the amount of 2% salt solution.
2A%2B7%2820%29=4%28A%2B20%29
2A%2B140=4A%2B80
-2A=-60
A=30gallons



Distributive-associative-commutative-properties/345844: how do you rewrite 2a+4b
1 solutions

Answer 247454 by Fombitz(13828) About Me  on 2010-09-21 09:39:03 (Show Source):


Triangles/345977: if the perimeter of an isosceles triangle is 48 inches and the length of the base is 10 what is the length of one of the legs?

1 solutions

Answer 247453 by Fombitz(13828) About Me  on 2010-09-21 09:37:50 (Show Source):
You can put this solution on YOUR website!
The perimeter of the isoceles triangle is,
P=x%2Bx%2B10=48
2x%2B10=48
2x=38
highlight%28x=19%29 inches


Geometry_Word_Problems/346000: Suppose a wire is stretched tightly around Earth. (The radius of Earth is approximately 6400Km). Then suppose the wire is cut and its length is increased by 20 km. It is then placed back around the planet so that it is the same distance from Earth at every point. Could you walk under the wire?
1 solutions

Answer 247452 by Fombitz(13828) About Me  on 2010-09-21 09:36:40 (Show Source):
You can put this solution on YOUR website!
Treat the Earth as a sphere.
The perimeter would be the circumference of a circle with radius 6400 km.
C=2%2Api%2A6400
C%5B1%5D=40212km
Now if we add 20 km,
C%5B2%5D=40212%2B20
C%5B2%5D=40232km
Find the radius of the circle with that perimeter,
2%2Api%2AR=40232
R=6403 km
The difference in radii is
dR=6403-6400
dR=3km
You could easily fit yourself under that, in fact, on a cloudy day you wouldn't even see the wire.


Polynomials-and-rational-expressions/346076: State the number of positive real zeros, negative real zeros, and imaginary zeros for g(x)=9x^3-7x^2+10-4
Thank you s much for all of your help!!!!
1 solutions

Answer 247449 by Fombitz(13828) About Me  on 2010-09-21 09:31:39 (Show Source):
You can put this solution on YOUR website!
I assume you mean g%28x%29=9x%5E3-7x%5E2%2B10x-4
.
.
.
graph%28300%2C300%2C-10%2C10%2C-10%2C10%2C9x%5E3-7x%5E2%2B10x-4%29
.
.
.
From the graph, there is one positive real zero, which means the remaining two roots are imaginary.


Age_Word_Problems/345990: Frank is 27 yrs younger than his mom. In 15 years, Frank will be half as old as his mother is then. How old his Frank and his mom now?
1 solutions

Answer 247448 by Fombitz(13828) About Me  on 2010-09-21 09:28:19 (Show Source):
You can put this solution on YOUR website!
1.F=M-27
In 15 years, Frank will be F%2B15 and his mom will be M%2B15.
F%2B15=%281%2F2%29%28M%2B15%29
2.2F=M-15
Substitute from eq. 1,
2%28M-27%29=M-15
2M-54=M-15
M=54-15
M=39
.
.
F=39-27
F=12
.
.
.
Frank is 12 and Mom is 39.


Permutations/345979: Suppose that a shipment of 120 electronic components contains 4 defective components to determine whether the shipment should be accepted, a quality control engineer randomly selects 4 of the components and test them. If 1 or more of the components is defective, the shipment is rejected. What is the probability that the shipment is rejected?
1 solutions

Answer 247443 by Fombitz(13828) About Me  on 2010-09-21 09:23:39 (Show Source):
You can put this solution on YOUR website!
P(Bad)=4/120=1/30
P(Good)=29/30
.
.
.
P(all 4 Good)=P(Good)*P(Good)*P(Good)*P(Good)
P(4G)=%2829%2F30%29%5E4=707281%2F810000=0.873
P(not 4G)=1-0.873=0.127
The probability of rejection is then P=0.127.


Money_Word_Problems/345984: A broker invested $24,000 in two mutual fnds, one earning 9% annual interest and the other earning 10%. After 1 year, the combined interest income is $2117. How much was invested at each rate?
1 solutions

Answer 247441 by Fombitz(13828) About Me  on 2010-09-21 09:17:42 (Show Source):
You can put this solution on YOUR website!
Let A be tha mount at 9%, B the amount at 10%.
Total amount invested:
1.A%2BB=24000
Total interest received:
2.9A%2B10B=211700
Multiply eq. 1 by (-10) and add to eq. 2,
-10A-10B%2B9A%2B10B=-240000%2B211700
-A=-28300
A=28300
Something is wrong with your numbers because that amount is greater than the total invested amount.
If the entire amount was invested at 10%, the interest would be $2400.
If the entire amount was invested at 9%, the interest would be $2160.
Your interest amount is outside of the possible range.
Check your numbers and re-post.


Word_Problems_With_Coins/346013: Jim has $9.00 in dimes and quarters. If he has twice as many quarters as dimes, how many of each coin does he have?
1 solutions

Answer 247437 by Fombitz(13828) About Me  on 2010-09-21 09:10:18 (Show Source):
You can put this solution on YOUR website!
Let D be the number of dimes, Q the number of quarters.
1.10D%2B25Q=900
2.Q=2D
Substitute eq. 2 into eq. 1,
10D%2B25%282D%29=900
10D%2B50D=900
60D=900
highlight%28D=15%29
Then from eq. 2,
Q=2%2815%29
highlight%28Q=30%29


real-numbers/345985: 13x-7=27 and then ROund to the nearest hundreth
1 solutions

Answer 247435 by Fombitz(13828) About Me  on 2010-09-21 09:07:34 (Show Source):
You can put this solution on YOUR website!
13x-7=27
13x=34
x=34%2F13 or approximately,
x=2.62


Geometry_Word_Problems/345998: The length of a fenced rectangular garden is 6 feet longer than the width. If the length of the fence used to surround the garden is 80 feet, what are the dimensions on the garden?
1 solutions

Answer 247434 by Fombitz(13828) About Me  on 2010-09-21 09:06:44 (Show Source):
You can put this solution on YOUR website!
For a rectangle,
P=2L%2B2W
L=6%2BW
Substitute,
2%286%2BW%29%2B2W=80
12%2B2W%2B2W=80
4W=68
highlight%28W=17%29feet
Then,
L=6%2B17
highlight%28L=23%29feet


Mixture_Word_Problems/345999: How much of an alloy that is 20% copper should be mixed with 600 ounces of an alloy that is 70% copper in order to get an alloy that is 30% copper?
1 solutions

Answer 247433 by Fombitz(13828) About Me  on 2010-09-21 09:04:45 (Show Source):
You can put this solution on YOUR website!
Let A be the amount of 20% copper.
20A%2B70%28600%29=30%28A%2B600%29
20A%2B42000=30A%2B18000
-10A=-24000
A=2400ounces


Inequalities/345997: |3z-2|+8=1
1 solutions

Answer 247432 by Fombitz(13828) About Me  on 2010-09-21 09:02:59 (Show Source):
You can put this solution on YOUR website!
abs%283z-2%29%2B8=1
abs%283z-2%29=-7
No solution, abs%28Y%29%3E=0 for any Y.


Circles/346024: P, Q and R are three points on a circle. If the ratio of arc pq:qr:pr = 3:4:5, find the measures of arc PR, QR and PS.
1 solutions

Answer 247430 by Fombitz(13828) About Me  on 2010-09-21 09:00:01 (Show Source):
You can put this solution on YOUR website!
PQ%2BQR%2BRP=360
3x%2B4x%2B5x=360
12x=360
highlight%28x=30%29
.
.
PQ=3x=90degrees
QR=4x=120degrees
RP=5x=150degrees


Rational-functions/346049:
1 solutions

Answer 247429 by Fombitz(13828) About Me  on 2010-09-21 08:57:09 (Show Source):
You can put this solution on YOUR website!
Please re-post.


Polynomials-and-rational-expressions/346037: Simplify: 2+i/l-3i
Thank you so much for all of your help!!!!
1 solutions

Answer 247428 by Fombitz(13828) About Me  on 2010-09-21 08:56:45 (Show Source):


Numbers_Word_Problems/346038: make 5 odd digits that add up to 14
1 solutions

Answer 247427 by Fombitz(13828) About Me  on 2010-09-21 08:52:50 (Show Source):
You can put this solution on YOUR website!
Can't be done.
.
.
.
Odd+Odd=Even
Odd+Even=Odd
Even+Even=Even
.
.
.
(Odd+Odd)+(Odd+Odd)+Odd=(Even)+(Even)+Odd=Even+Odd=Odd


Expressions-with-variables/346041: simplify : y^4 *y^3*y
1 solutions

Answer 247425 by Fombitz(13828) About Me  on 2010-09-21 08:48:58 (Show Source):


Expressions-with-variables/346045: help! rewrite without an exponent:
(9/4)^2 = 16/81?
1 solutions

Answer 247424 by Fombitz(13828) About Me  on 2010-09-21 08:47:59 (Show Source):
You can put this solution on YOUR website!
No.
%289%2F4%29%5E2+=+%289%2A9%29%2F%284%2A4%29
%289%2F4%29%5E2=highlight%2881%2F16%29
.
.
.
How'd your answer get inverted?


Linear-equations/346048: i need help on these probloms.5g+h=g,for g

1 solutions

Answer 247423 by Fombitz(13828) About Me  on 2010-09-21 08:46:48 (Show Source):


Mixture_Word_Problems/346060: a radiator holds 12 qt of liquid. How many quarts of pure antifreeze and how many quarts of 40% antiffreeze solution must be mixed to fill the radiator with a 50% antifreeze solution?
1 solutions

Answer 247421 by Fombitz(13828) About Me  on 2010-09-21 08:45:44 (Show Source):
You can put this solution on YOUR website!
Let A be the amount of pure antifreeze and B the amount of 40% solution.
Total amount equation:
1.A%2BB=12
Concentration equation:
100A%2B40B=50%2812%29
100A%2B40B=600
2.5A%2B2B=30
Multiply eq. 1 by (-2) and add to eq. 2,
-2A-2B%2B5A%2B2B=-24%2B30
3A=6
highlight%28A=2%29quarts
Then from eq. 1,
2%2BB=12
highlight%28B=10%29quarts


Exponents-negative-and-fractional/346050: factor: 81-64v^2
1 solutions

Answer 247419 by Fombitz(13828) About Me  on 2010-09-21 08:38:26 (Show Source):
You can put this solution on YOUR website!
Recognize that the expression is the difference of two squares.
81-64v%5E2=%289-8v%29%289%2B8v%29


Polynomials-and-rational-expressions/346051: Write a quadratic equation with -3/4 and 4 as its roots. write the equation in form ax^2+bx+c=0, where a, b, and c are integers.
Thank you so much for all of your help!!!!
1 solutions

Answer 247417 by Fombitz(13828) About Me  on 2010-09-21 08:37:09 (Show Source):
You can put this solution on YOUR website!
The simplest quadratic equation with these roots is,
%28x%2B3%2F4%29%28x-4%29=0
Multiply both sides by 4.
4%28x%2B3%2F4%29%28x-4%29=0
%284x%2B3%29%28x-4%29=0
Use the FOIL method to expand,
4x%5E2-16x%2B3x-12=0
highlight%284x%5E2-13x-12=0%29


expressions/346058: how do i solve the following problem? (3x-1)^2=75
1 solutions

Answer 247416 by Fombitz(13828) About Me  on 2010-09-21 08:33:57 (Show Source):


Numbers_Word_Problems/345969: One sixth of a number minus one seventh of the same number is 1. What is the number?
So far I have 1/6x-1/7x=1
1 solutions

Answer 247382 by Fombitz(13828) About Me  on 2010-09-20 23:04:14 (Show Source):
You can put this solution on YOUR website!
So far so good.
Multiply both sides by 7%2A6=42 to get rid of the fractions.
Then solve for x.


Radicals/345905: The section we are doing is "Simplifying Radical Expressions"
And the problem is:
negative sign, then sqrt 20ab^6
Please help....thank you for your time
1 solutions

Answer 247380 by Fombitz(13828) About Me  on 2010-09-20 23:03:17 (Show Source):