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1 solutions
Answer 340605 by nerdybill(6958)   on 2011-10-01 16:45:15 (Show Source):
You can put this solution on YOUR website!The measure of the supplement of an angle is 60 less than three times the measure of the complement of the angle. Find the measure of the angle.
.
Let x = measure of angle
then
90-x = complement of angle
180-x = supplement of angle
.
180-x = 3(90-x) - 60
180-x = 270-3x - 60
180-x = 210-3x
180+2x = 210
2x = 30
x = 15 degrees
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Percentage-and-ratio-word-problems/507505: I am trying to help my nephew with a word problem and am having trouble coming up with the equation. Could you please help me? Thank you.
If an entire job can be done in 5 hours and 20 minutes how much of the job can be done in one hour. The equation is supposed to be in fractions.
Thank you.
1 solutions
Answer 340498 by nerdybill(6958) on 2011-10-01 09:53:51 (Show Source):
You can put this solution on YOUR website!If an entire job can be done in 5 hours and 20 minutes how much of the job can be done in one hour. The equation is supposed to be in fractions.
.
5 hours and 20 minutes is the same as:
5 + 20/60
5 + 1/3
15/3 + 1/3
16/3 hours
.
your equation is:
"time" * "rate"
"time" is one hour
"rate" is 1 job per 16/3 hours
.
1(1/(16/3))
1(3/16)
3/16 of the entire job can be done in an hour
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Miscellaneous_Word_Problems/507432: a baseball is hit so that its height in feet after t seconds is s(t)=-16tsquared +44t+4 find the maximum height of the baseball
1 solutions
Answer 340497 by nerdybill(6958) on 2011-10-01 09:49:05 (Show Source):
You can put this solution on YOUR website!a baseball is hit so that its height in feet after t seconds is s(t)=-16tsquared +44t+4 find the maximum height of the baseball
.
s(t)=-16tsquared +44t+4
s(t)=-16t^2 +44t+4
.
Because the coefficient associated with the t^2 term is negative, we know it is a parabola that opens downwards.
.
therefore, the vertex is the max.
.
height is max when:
t = -b/(2a)
t = -44/(2(-16))
t = -44/(-32)
t = 1.375 secs
.
max height:
s(t)=-16t^2 +44t+4
s(1.375)=-16(1.375)^2 +44(1.375)+4
s(1.375)=-16(1.890625) +60.5+4
s(1.375)=-30.25 +60.5+4
s(1.375)= 34.25 feet
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Percentage-and-ratio-word-problems/507450: How many gallons of a 60% antifreeze solution must be mixed with 90 gallons of 10% antifreeze to get a mixture that is 50% difference?
1 solutions
Answer 340491 by nerdybill(6958) on 2011-10-01 09:35:33 (Show Source):
You can put this solution on YOUR website!How many gallons of a 60% antifreeze solution must be mixed with 90 gallons of 10% antifreeze to get a mixture that is 50% difference?
.
Let x = amount (gallons) of 60% antifreeze
then
.60x + .10(90) = .50(x+90)
.60x + 9 = .50x+45
.10x + 9 = 45
.10x = 36
x = 360 gallons
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Linear-equations/507452: the given conditions to write an equation for the line in point-slope form.
{{slope=6/7, passing through (8,7)}} is the answer y+7=6/7 (x+8)
1 solutions
Answer 340490 by nerdybill(6958) on 2011-10-01 09:31:47 (Show Source):
You can put this solution on YOUR website!the given conditions to write an equation for the line in point-slope form.
{{slope=6/7, passing through (8,7)}} is the answer y+7=6/7 (x+8)
.
"point-slope" form is:
y - y1 = m(x - x1)
plugging in given values:
y - 7 = 6/7(x - 8)
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Polynomials-and-rational-expressions/507465: Bob's Barber Shop estimates their gross revenue for the second quarter to be given by the polynomial 7x^3 - 9x^2 - 2x + 4. The shop estimated their cost for that quarter to be given by x^2 + 7x - 5. For the second quarter find and simplify a polynomial that will represnt their profit.
1 solutions
Answer 340489 by nerdybill(6958) on 2011-10-01 09:28:00 (Show Source):
You can put this solution on YOUR website!Bob's Barber Shop estimates their gross revenue for the second quarter to be given by the polynomial 7x^3 - 9x^2 - 2x + 4. The shop estimated their cost for that quarter to be given by x^2 + 7x - 5. For the second quarter find and simplify a polynomial that will represnt their profit.
.
Profit is
"revenue" - "cost"
(7x^3 - 9x^2 - 2x + 4) - (x^2 + 7x - 5)
7x^3 - 9x^2 - 2x + 4 - x^2 - 7x + 5
7x^3 - 10x^2 - 2x + 4 - 7x + 5
7x^3 - 10x^2 - 9x + 4 + 5
7x^3 - 10x^2 - 9x + 9
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Money_Word_Problems/507473: A delivery truck arrives at the Robert's store with 8 small boxes and 5 large boxes. The total charge for the boxes, without the tax and delivery charges, is 184 pesos. A large box cost 3 pesos more than a small box. What is the cost of each box?
1 solutions
Answer 340487 by nerdybill(6958) on 2011-10-01 09:22:43 (Show Source):
You can put this solution on YOUR website!A delivery truck arrives at the Robert's store with 8 small boxes and 5 large boxes. The total charge for the boxes, without the tax and delivery charges, is 184 pesos. A large box cost 3 pesos more than a small box. What is the cost of each box?
.
Let x = cost (pesos) of small box
then
x+3 = cost (pesos) of large box
.
8x + 5(x+3) = 184
8x + 5x+15 = 184
13x+15 = 184
13x = 169
x = 13 pesos (small box)
.
Large box:
x+3 = 13+3 = 16 pesos
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Linear-equations/507177: What is 8x - 5y = 15 in slope intercept form
1 solutions
Answer 340362 by nerdybill(6958) on 2011-09-30 08:59:06 (Show Source):
You can put this solution on YOUR website!What is 8x - 5y = 15 in slope intercept form
.
"Slope-intercept" form is:
y = mx + b
where
m is the slope
b is the y-intercept at (0,b)
.
8x - 5y = 15
-5y = -8x + 15
5y = 8x - 15
y = (8/5)x - 3 (this is what they're looking for)
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Money_Word_Problems/507180: a man invest twice as much as 8% as he invests at 5%.his total annual income from the two investments is 840.how much is invested at each rate?
1 solutions
Answer 340361 by nerdybill(6958) on 2011-09-30 08:57:24 (Show Source):
You can put this solution on YOUR website!a man invest twice as much as 8% as he invests at 5%.his total annual income from the two investments is 840.how much is invested at each rate?
.
Let x = amount ($) invested at 5%
then
2x = amount ($) invested at 8%
.
.05x + .08(2x) = 840
.05x + .16x = 840
.21x = 840
x = 840/.21
x = $4000 (amount invested at 5%)
.
amount invested at 8%:
2x = 2(4000) = $8000
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Rate-of-work-word-problems/507078: Joe and Moe can mow the lawn in 26 minutes if they work together. If Moe works twice as fast as Joe, how long does it take Joe to mow the lawn alone?
1 solutions
Answer 340331 by nerdybill(6958) on 2011-09-29 23:23:39 (Show Source):
You can put this solution on YOUR website!Joe and Moe can mow the lawn in 26 minutes if they work together. If Moe works twice as fast as Joe, how long does it take Joe to mow the lawn alone?
.
Let J = time (minutes) Jo takes to mow alone
then
2j = time Moe takes
.
26(1/J + 1/(2J)) = 1
multiplying both sides by 2J:
26(2 + 1) = 2J
26(3) = 2J
[26(3)]/2 = J
[13(3)] = J
39 minutes = J (Jo's time)
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Rate-of-work-word-problems/506533: One man can paint a garage in 28 hours. After working for 12 hours, he was given a new job, and a second man finished painting in 18 hours. How long would the second man take take to paint to whole garage?
1 solutions
Answer 340191 by nerdybill(6958) on 2011-09-29 09:01:10 (Show Source):
You can put this solution on YOUR website!One man can paint a garage in 28 hours. After working for 12 hours, he was given a new job, and a second man finished painting in 18 hours. How long would the second man take take to paint to whole garage?
.
Let x = time (hours) it takes second man to paint whole garage
then
12(1/28) + 18(1/x) = 1
multiplying both sides by 28x:
12(x) + 18(28) = 28x
12x + 504 = 28x
504 = 16x
31.5 hours = x
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Volume/505914: What is the volume of a box with a length of 14 cm, a width of 10 cm, and a height of 8 cm?
1 solutions
Answer 340008 by nerdybill(6958) on 2011-09-28 10:50:58 (Show Source):
You can put this solution on YOUR website!What is the volume of a box with a length of 14 cm, a width of 10 cm, and a height of 8 cm?
volume = length*width*height
volume = 14*10*8 = 1120 cubic cm
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Rate-of-work-word-problems/505268: A bath tub can be filled by the hot and cold water pipes in 4 minutes, and when full it can be emptied by the waste pipe in 5 minutes. If it is half full, and all three pipes are set running, when will the tub be filled?
1 solutions
Answer 339840 by nerdybill(6958) on 2011-09-27 12:26:55 (Show Source):
You can put this solution on YOUR website!A bath tub can be filled by the hot and cold water pipes in 4 minutes, and when full it can be emptied by the waste pipe in 5 minutes. If it is half full, and all three pipes are set running, when will the tub be filled?
.
Let t = time (mins) tub is filled
then
t(1/4 - 1/5)= 1/2
multiplying both sides by 20:
t(5 - 4)= 10
t(1)= 10
t = 10 minutes
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Circles/505281: I am trying to determine if this equation is a circle and give center and radius. I know it is a circle because x and y have equal coefficients and I know the formula but I can't figure how to set it up. Equation is: x^2+y^2-12x+10y = -25. Thank you
1 solutions
Answer 339836 by nerdybill(6958) on 2011-09-27 12:00:08 (Show Source):
You can put this solution on YOUR website!equation of a circle:
(x - h)^2 + (y - k)^2 = r^2
.
For your problem:
x^2+y^2-12x+10y = -25
group x's and y's:
(x^2-12x)+(y^2+10y) = -25
complete the squares:
(x^2-12x+36)+(y^2+10y+25) = -25+36+25
(x-6)^2+(y+5)^2 = 36
(x-6)^2+(y+5)^2 = 6^2
.
Center: (6,5)
Radius: 6
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Rate-of-work-word-problems/505214: Together Sophie and Clarissa can paint a house in 6 days. It takes Clarissa 5 days less than Sophie to paint the house by herself. How many days does it take Sophie to paint the house by herself?
1 solutions
Answer 339817 by nerdybill(6958) on 2011-09-27 08:55:43 (Show Source):
You can put this solution on YOUR website!Together Sophie and Clarissa can paint a house in 6 days. It takes Clarissa 5 days less than Sophie to paint the house by herself. How many days does it take Sophie to paint the house by herself?
.
Let x = time (days) it takes for Sophie to do it alone
then
x-5 = time it takes for Clarissa
.
6(1/x + 1/(x-5)) = 1
multiplying both sides by x(x-5):
6(x-5 + x) = x(x-5)
6(2x-5) = x(x-5)
12x-30 = x^2-5x
-30 = x^2-17x
0 = x^2-17x+30
0 = (x-15)(x-2)
x = {15, 2}
the 2 won't make sense, throw it out leaving:
x = 15 days (Sophie's time)
.
Clarissa:
x-5 = 15-5 = 10 days
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Linear-equations/504708: Can you put this in standard form? slope= 5/6;(22,12)
1 solutions
Answer 339683 by nerdybill(6958) on 2011-09-26 15:51:43 (Show Source):
You can put this solution on YOUR website!Can you put this in standard form? slope= 5/6;(22,12)
.
plug given data into "point-slope" form:
y - y1 = m(x - x1)
y - 12 = (5/6)(x - 22)
y - 12 = (5/6)x - (5/6)22
y - 12 = (5/6)x - (5/3)11
y - 12 = (5/6)x - 55/3
y = (5/6)x - 55/3 + 12
y = (5/6)x - 55/3 + 36/3
y = (5/6)x - 19/3 ("slope-intercept" form)
-(5/6)x + y = - 19/3
-(5/6)x + y = -19/3 ("standard" form)
OR
-5x/6 + y = -19/3 ("standard" form)
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Equations/504695: Hi I am in the 8th grade and I am not good at algebra at all but I know I have to learn it. Can you help me solve this equation: 3[8+(4+2)]=
Can you tell me how to solve this is layman terms because I want to learn how to do it myself.
1 solutions
Answer 339682 by nerdybill(6958) on 2011-09-26 15:36:42 (Show Source):
You can put this solution on YOUR website!You would apply the "order of operations"
A memory device is:
PEMDAS(please excuse my dear aunt sally)
.
P: parentheses first
E: exponents next
MD: multiplication/division from left to right
AS: addition/subtraction from left to right
.
3[8+(4+2)]
3[8+6]
3[14]
42
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Linear-equations/504586: find the equation of the line passing through (-1, 2) and parallet to 2x-4y = 24
1 solutions
Answer 339651 by nerdybill(6958) on 2011-09-26 12:24:24 (Show Source):
You can put this solution on YOUR website!find the equation of the line passing through (-1, 2) and parallel to 2x-4y = 24
.
Two lines are parallel if they have the same slope.
First, find slope of:
2x-4y = 24
-4y = -2x+24
4y = 2x-24
y = (1/2)x-6
slope is 1/2
.
plug slope (1/2) and given point (-1, 2) into "point-slope" form:
y - y1 = m(x -x1)
y - 2 = (1/2)(x -(-1))
y - 2 = (1/2)(x + 1)
y - 2 = (1/2)x + 1/2
y = (1/2)x + 1/2 + 2
y = (1/2)x + 1/2 + 4/4
y = (1/2)x + 5/2 (this is what they're looking for)
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Expressions-with-variables/503768: a number raised to the third power multiplied by 125 is equal to 1/8 . what is the number?
1 solutions
Answer 339426 by nerdybill(6958) on 2011-09-25 09:28:42 (Show Source):
You can put this solution on YOUR website! a number raised to the third power multiplied by 125 is equal to 1/8 . what is the number?
.
Let x = the number
then
(x^3)(125) = 1/8
x^3 = 1/(8*125)
x^3 = 1/(1000)
x^3 = 1/(10*10*10)
take cube root of both sides:
x = 1/10
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Expressions-with-variables/503767: katrina can design a 3 feet by 3 feet board using egg shells in 3 hours.her cousin,pia volunteered to help katrina.if they work together,it will take them 1 hour and 40 minutes to finish the job.how long does it take pia to do the job done?
1 solutions
Answer 339423 by nerdybill(6958) on 2011-09-25 09:21:01 (Show Source):
You can put this solution on YOUR website!katrina can design a 3 feet by 3 feet board using egg shells in 3 hours.her cousin,pia volunteered to help katrina.if they work together,it will take them 1 hour and 40 minutes to finish the job.how long does it take pia to do the job done?
.
Let x = time (minutes) it takes pia alone
then
time it takes for both:
1 hour and 40 minutes = 100 minutes
.
katrina's rate: 1/180
.
100(1/180 + 1/x) = 1
multiplying both sides by 180x:
100(x + 180) = 180x
100x + 18000 = 180x
18000 = 80x
225 minutes = x
or
3 hours and 45 minutes = x (pia doing it alone)
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