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scott8148 answered: 6619 problems
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????List all possible whole number measurements for length and width for a rectangle with an area of 20 feet.
1 solutions
Answer 361527 by scott8148(6628)   on 2012-01-09 20:28:20 (Show Source):
You can put this solution on YOUR website!these are the whole number factor pairs of 20
1 , 20
2 , 10
4 , 5
5 , 4
10 , 2
20 , 1
the duplicate pairs may not apply in your case (if length is considered to be the "longest" measurement)
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Linear_Equations_And_Systems_Word_Problems/551505: James is four years younger than Austin. If three times James' age is increased by the square of Austin's age, the result is 28. Find the ages of James and Austin. (Algebraic solutions only)
1 solutions
Answer 359765 by scott8148(6628) on 2012-01-01 19:49:12 (Show Source):
You can put this solution on YOUR website!"James is four years younger than Austin" ___ j = a - 4
"If three times James' age is increased by the square of Austin's age, the result is 28"
___ 3j + a^2 = 28
substituting ___ 3(a - 4) + a^2 = 28 ___ a^2 + 3a - 40 = 0 ___ (a + 8)(a - 5) = 0
solve for a, then substitute back to find j
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Linear-equations/551481: So I have been doing some workbooks to refresh myself in algebra lately to get back into school and a ran into a problem that for the life of me I cannot understand, its a Linear Equation that in order to find the value of X you have to eliminate the fractions to break it down, now the question in the book reads:
"Solve The Following Equation: 5 - (1/6)x = {-(2/3)}x "
now i have worked it down several times but it never matched what the answer in the workbook of " 30-x=9x "
from what the book says it should be its easy to find the solution is " X=3 " but when I work down the original equation I get this:
5 - (1/6)x = {-(2/3)}x ***convert to fractions**
5/1 - x/6 = -(3x/2) **next multiplied each term by the LCD of 6,or 6/1**
5/1*6/1 - x/6*6/1 = {-(3x/2)}*6/1 ***ok......
here is where i am confused, after canceling out the denominators my ending equation is " 30-x= -9x " now it has been along time since i have done any math assignments but i thought a negative multiplied by a positive stayed a negative # but my book says it becomes positive? is that right? Is -3x*6= to 9x? if so why? i thought like-signs always made a positive in multiplication
1 solutions
Answer 359757 by scott8148(6628) on 2012-01-01 19:36:57 (Show Source):
You can put this solution on YOUR website!not wishing to demean your book, but...substituting the "solution" into the original equation
5 - (1/6)(3) = {-(2/3)}(3) ___ 5 - (1/2) = -(6/3)...I don't think so...
"Solve The Following Equation: 5 - (1/6)x = {-(2/3)}x "
multiplying by 6 to clear fractions ___ 30 - x = -4x ___ x = -10
something is amiss, but what?
the only "glitch" I could see is ___ how did {-(2/3)}x become (-3x/2) between your 1st and 2nd step?
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test/551297: The value of certain two digit number is four less than six times the sum of it's digits. If the digits of the number are reversed, the resulting number is nine less than the original number. Find the number. Please help me!!!!
1 solutions
Answer 359605 by scott8148(6628) on 2011-12-31 16:20:52 (Show Source):
You can put this solution on YOUR website!t = tens digit , u = units digit
"The value of certain two digit number is four less than six times the sum of it's digits"
___ 10t + u + 4 = 6(t + u)
"If the digits of the number are reversed, the resulting number is nine less than the original number"
___ 10u + t + 9 = 10t + u ___ 9u + 9 = 9t ___ u + 1 = t
substituting ___ 10(u + 1) + u + 4 = 6[(u + 1) + u] ___ 11u + 14 = 12u + 6
solve for u, then substitute back to find t ___ the number is "tu"
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Metalworking/551262: Ok I need steps for the question " a store allows customers to buy 3 iteams of the same price and get 2 more of the same iteams free. What percent savings does this represent.
The answer is 40 but i need steps im only 12 so make the steps easy. thanks :p
1 solutions
Answer 359576 by scott8148(6628) on 2011-12-31 13:16:52 (Show Source):
You can put this solution on YOUR website!putting in numbers may make it easier
3 items at $1.00 each, plus 2 free is 5 items for $3.00
5 items for $3.00 is $.60 each ($3.00 / 5)
the $.60 price is 60% of the $1.00 price [($.60 / $1.00) * 100%]
100% (full price) minus 60% (sale price) equals 40% savings
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Age_Word_Problems/551211: A father is 24 years older than his son. In 8years he will be twice as old as his son. Determine their present ages. Please, Thank you~
1 solutions
Answer 359573 by scott8148(6628) on 2011-12-31 13:03:44 (Show Source):
You can put this solution on YOUR website!"A father is 24 years older than his son" ___ f = s + 24
"In 8 years he will be twice as old as his son" ___ f + 8 = 2(s + 8)
substituting ___ (s + 24) + 8 = 2s + 16
solve for s, and substitute back to find f
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Coordinate-system/551001: A straight line makes on the co-ordinate axes positive intercepts whose sum is 5.If the positive line passes through the point P(-3,4),find its equation.pls....help me.
1 solutions
Answer 359343 by scott8148(6628) on 2011-12-30 10:52:56 (Show Source):
You can put this solution on YOUR website!let the y-intercept equal (j,0)
let the x-intercept equal (k,0)
"positive intercepts whose sum is 5" ___ j + k = 5 ___ k = 5 - j
using slope-intercept, the equation of the line will be ___ y = (-j / k)x + j
y - j = (-j / k)x
substituting ___ y - j = [-j / (5 - j)]x
substituting point P ___ 4 - j = [-j / (5 - j)](-3)
(4 - j)(5 - j) = 3j ___ j^2 - 9j + 20 = 3j ___ j^2 - 12j + 20 = 0 ___ (j - 10)(j - 2) = 0
j = 10 ___ and ___ j = 2 ___ (10 is too big)
substitute back with the value of j to find k, then put the values into the slope-intercept equation
for "standard" form
___ multiplying by k ___ ky = -jx + jk
___ adding jx ___ jx + ky = jk
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Graphs/550933: my instructions are to write an equation that is parallel to the given line passes through the given point Here is the problem- 3x+4y=8; (4,-3) how would i solve this
1 solutions
Answer 359236 by scott8148(6628) on 2011-12-29 18:14:54 (Show Source):
You can put this solution on YOUR website!the slope of a line is determined by the ratio of the x and y coefficients
a parallel line has the same slope, so the same coefficients can be used
the thing that changes is the position of the line in the coordinate system
that is determined by the constant term ___ 8 in this case
to find the new constant term for the parallel line, substitute the given point into the equation
3x + 4y = ? ___ 3(4) + 4(-3) = ?
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Rate-of-work-word-problems/550903: the amount of time it takes to paint a house varies inversly with the number of painters. if it takes 4 painters 40 hours how long would it take 10 painters?
A.100 HOURS B.26 HOURS C.20 HOURS D.16 HOURS ...... how did you get the answer?
1 solutions
Answer 359213 by scott8148(6628) on 2011-12-29 16:39:50 (Show Source):
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Travel_Word_Problems/550807: A train left the station at 9 AM travelling at 50mph. At 11 PM an airplane left the same station in the same direction at 175mph. At what time did the airplane overtake the train?
1 solutions
Answer 359210 by scott8148(6628) on 2011-12-29 16:36:28 (Show Source):
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Exponential-and-logarithmic-functions/550851: I have a polynomial regression and I am trying to build a calculation to solve for x. The equation I am looking at is x^2+x+b=y. I can calculate the y easy enough, but writing an excel formula to determine X has got me beat.
thanks
1 solutions
Answer 359206 by scott8148(6628) on 2011-12-29 16:32:30 (Show Source):
You can put this solution on YOUR website!this is an application of the quadratic formula
x^2 + x + (b - y) = 0
x = {-1 ± [sqrt(1 - 4(b - y))]} / 2
the ± may generate two values for x; you probably want two equations, one + and one -
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Mixture_Word_Problems/550477: how many quarts of pure anti-freeze must be added to 7 quarts of a 20% antifreeze solution to obtain a 30% anti-freeze solution?
__Quart(s )of pure antifreeze must be added.
1 solutions
Answer 358792 by scott8148(6628) on 2011-12-27 17:13:20 (Show Source):
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Travel_Word_Problems/550492: Two cars leave the same point traveling in opposite directions. The second car travels 15 mph faster than the first. After 3 hours they are 465 miles apart. How fast is each car traveling?
1 solutions
Answer 358790 by scott8148(6628) on 2011-12-27 17:10:32 (Show Source):
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Mixture_Word_Problems/550481: Paul has an 70% methyl alcohol solution. He wishes to make a gallon of a solution by mixing his methyl alcohol solution with water. If 128 ounces, or a gallon, of solution should contain 7% methyl alcohol, how much of the 70% methyl alcohol solution and how much water must be mixed?
The amount of 70% methyl alcohol solution is ___ounces.
(Type an integer or a decimal.)
1 solutions
Answer 358789 by scott8148(6628) on 2011-12-27 17:08:16 (Show Source):
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Linear-systems/550486: HHHHEEELLLPPPP.....one more please??? solve using substitution method......5x + 7y = -23 and -8x + y = 49 type an ordered pair
1 solutions
Answer 358788 by scott8148(6628) on 2011-12-27 17:03:23 (Show Source):
You can put this solution on YOUR website!y = 49 + 8x
substituting ___ 5x + 7(49 + 8x) = -23 ___ 5x + 343 + 56x = -23
solve for x, and then substitute back to find y
(use any equation that has both x and y)
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Mixture_Word_Problems/550491: A chemist has two solutions of HCL. One has a 40% concentration and the other has a 25% concentration. How many liters of each solution must be mixed to obtain 54 liters of a 39% solution?
1 solutions
Answer 358787 by scott8148(6628) on 2011-12-27 16:59:13 (Show Source):
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Divisibility_and_Prime_Numbers/550489: Factor the expression 49x^2-42xy+9b^2
I got the answer (7x-3y)(7x-3y), something tells me this is wrong however. I've worked on it for the last 3 hours now and just need some help I guess.
1 solutions
Answer 358786 by scott8148(6628) on 2011-12-27 16:57:06 (Show Source):
You can put this solution on YOUR website!if the expression is written correctly, it is not factorable
if it is this "49x^2-42xy+9y^2"' then your factors are correct
if it is this "49x^2-42xb+9b^2"' then the factors are ___ (7x-3b)(7x-3b)
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Quadratic_Equations/550390: the speed of a boat in still water is 15 km/hr. it needs four more hours to travel 63 km against the current of a river than it needs to travel down the river. Determine the speed of the current of the river.
1 solutions
Answer 358725 by scott8148(6628) on 2011-12-27 11:28:45 (Show Source):
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Mixture_Word_Problems/550372: how many pounds of peanuts at 40 pesos per pound should be added to 100 pounds of cashew nuts at 100 pesos per pound if the mixture is to be worth 60 pesos per pound?
thanks i need it before january 2..
1 solutions
Answer 358723 by scott8148(6628) on 2011-12-27 11:19:24 (Show Source):
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expressions/549983: which of the following is a rational number?
a.√2
b.√pi(3.14)
c.√7
d.√5/√25
e.√64/√49
my act aNSWER key has e, i'm not sure if its right though and how it is a rational number. so an explanation would be much appreciated.
1 solutions
Answer 358273 by scott8148(6628) on 2011-12-23 11:06:50 (Show Source):
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Graphs/549973: A solution to the compound inequality 17 <= 3 - 2x <= 21 is given below. Choose the statement that is true about the given solution.
17 <= 3 - 2x and 3 - 2x <= 21 - LINE 1
20 <= -2x and -2x <= 24 - LINE 2
-10 => x and x => -12 - LINE 3
ANSWERS:
A: There is a mistake in line # 1.
B: There is a mistake in line # 2.
C: There is a mistake in line # 3.
D: There are no mistakes, the solution is correct.
Thank you in advance! so much!
1 solutions
Answer 358272 by scott8148(6628) on 2011-12-23 10:57:45 (Show Source):
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Quadratic-relations-and-conic-sections/549417: For the following equation, give the x-intercepts and the coordinates of the vertex.
y=x^2-6x-1
The chart needs to be filled out like this:
x-intercept (x,y)= (_____, _____) (smaller x-value)
x-intercept (x,y)= (_____, _____) (larger x-value)
vertex (x,y)= (_____, _____)
I cannot figure out how to fill out this chart please help me
1 solutions
Answer 357764 by scott8148(6628) on 2011-12-20 21:24:36 (Show Source):
You can put this solution on YOUR website!the x-intercepts are the roots of the equation (when y=0)
___ use the quadratic formula to find them
the vertex is on the axis of symmetry
___ the equation is ___ x = -b / (2a)
___ solve for x, then plug the value into the equation to find y
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Average/549448: I have a 64% in math. What grade do i need to get on my final which is 20% of my grade, to get at least a 69.5%?
1 solutions
Answer 357757 by scott8148(6628) on 2011-12-20 21:07:56 (Show Source):
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Systems-of-equations/549416: Please see how to solve the following algebra word problem. I do not know where to start.
A man bought 3 shirts and 8 pairs of slacks for $237. At the same store, another man bought 5 shirts and 3 pairs of slacks for $147. Find the cost of 1 shirt and 1 pair of slacks.
Thank you,
Natasha
1 solutions
Answer 357735 by scott8148(6628) on 2011-12-20 18:52:23 (Show Source):
You can put this solution on YOUR website!x = cost of shirts, y = cost of slacks
"A man bought 3 shirts and 8 pairs of slacks for $237" ___ 3x + 8y = 237
"another man bought 5 shirts and 3 pairs of slacks for $147" ___ 5x + 8y = 147
solve the system of equations for x and y
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Trigonometry-basics/549066: a giant redwood tree casts a shadow that is 532 feet long. find the height of the tree if the angle of elevation of the sun is 32 degrees. round your answer to the nearest foot..Thankss
1 solutions
Answer 357734 by scott8148(6628) on 2011-12-20 18:47:46 (Show Source):
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Triangles/548798: From the top of a lighthouse 50 meters high, the angle of depression of a boat out at sea has a measure of 15 degrees. Find to the nearest meter the distance from the boat to the foot of the lighthouse which is at sea level.
Explain too please
1 solutions
Answer 357731 by scott8148(6628) on 2011-12-20 18:39:24 (Show Source):
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Triangles/548801: Find to the nearest degree the measure of the angle of elevation of the sun when a student 170 centimeters tall casts a shadow 170 centimeters long.
Explain it too please.
1 solutions
Answer 357729 by scott8148(6628) on 2011-12-20 18:36:16 (Show Source):
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test/548760: Can you please tell me if i got these correct and if not which ones i got wrong thanks.
1. Factor 9x^2-64 completely.
(9x-8)(x+8)
2. Factor x^2-18x-144
x(x-180)-144
3. Solve 3x(x-5)(3x+5)=0
(0,5,-5/3)
4. Factor x^2+12x+27 completely
(x+3)(x+9)
5. Solve (3x-7)(x+2)=0
(7/3,-2)
6.) Solve 2x(x+4)(4x-9)=0
(0,-4,9/4)
For problems 7-9 the length of the rectangle is 3 inches more than its width.
7. Write an equation for the area of the rectangle in terms of width, w.
A=w^2+3
8. If the area of the rectangle is 180 square inches, write an equation for the above situation.
180=w^2+3
9. Write an equation for the situation above by multiplying the factors together and setting the equation equal to zero.
w^2+3-180=0
10. What are the factors of the equation w^2+3w-180
(w+15)(w-12)
For the problems 11-13 a projectile is fired upward with an initial speed of 800 feet per second. It is given that h=-16t^2+800t (h is the height of the ball)
11. Factor the given equation completely
h=(-16t)(t-50)
12. What will you set h equal to in the equation to find how many seconds it takes for the projectile to hit the ground
h=0
13. Find how many seconds before the projectile hits the ground. Let Yv1=-16t^2+800t
50 seconds
For problems 14-16 the equation d=.05^2+r models the distance, d , in feet traveled by a car moving r miles per hour after the driver begins to stop the car.
14. Factor the equation d=.05^2+r
d=r(.05+1)
15. What is the domain of the situation above?
All positive integers
16. If the distance the car traveled after applying the brakes equals 20 feet, what does that mean to the officer investigating the accident? (HINT: let d=20, bring 20 to the right so that the equation equals zero, identify the coefficients A,B, and C and then use the quadratic formula to solve)
The car was going about 32.36 miles per hour
For problems 17-18 the height, h, of the ball t seconds after it is released for a jump shot in a basketball game can be modeled with the equation h=-16t^2+12t+8.
17. The rim of the basket is 10 feet high. What is the correct way to set up the problem to solve when the ball reaches this height?
10=-16t^2+12t+8
18. State the number of solutions to the problem and state if the ball has a chance of going into the basket.
There are 2 solutions, meaning 2 times when the ball is 10 ft high. the time that the ball reaches 10 feet on its way up and on its way down. One of these times will be the balls opportunity to pass through the hoop.
1 solutions
Answer 357726 by scott8148(6628) on 2011-12-20 18:30:17 (Show Source):
You can put this solution on YOUR website!1, 2, 7, 8(because of 7), 9 ___ see 10 for hint for 7, 8, and 9
14-16 are unclear...
17 should probably be ___ 0 = -16t^2 + 12t - 2
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