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1 solutions
Answer 266784 by robertb(4012)   on 2010-11-22 19:36:03 (Show Source):
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Graphs/375132: i have to graph, y-3=0.6666666667(x+4),can you put it into slope-intercept form for me, i can then graph it thanks.
1 solutions
Answer 266782 by robertb(4012) on 2010-11-22 19:32:19 (Show Source):
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Graphs/375157: I can't remember graphing at all and am attempting to help my daughter with her home work. Can you explain how to solve the following problem so that I may understand and explain to her?
x=3y
Thank you!
Sam
1 solutions
Answer 266779 by robertb(4012) on 2010-11-22 19:28:51 (Show Source):
You can put this solution on YOUR website!This is a linear equation. To graph a linear equation, you need two points on the line. If x = 0, then y = 0. (Just substitute x=0 into the eqution.) If x = 3, then 3 = 3y, or y = 1. Hence two points on the line are (0,0) and (3,1). Plot these two points on the line and try your best two draw a straight line through them.
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Expressions-with-variables/375076: can anyone find the solution to this two part elimination method equation?
4x+5y=5
6x+7y=7
1 solutions
Answer 266772 by robertb(4012) on 2010-11-22 19:23:26 (Show Source):
You can put this solution on YOUR website!Multiply the top equation by -6: -24x-30y = -30
Multiply the bottom equation by 4: 24x + 28y = 28.
Add corresponding sides:
-2y = -2, or y = 1.
To find x, use either the top or the bottom equation. (I will use the top).
4x + 5 = 5, or 4x = 0, or x = 0.
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Rational-functions/375060: x-0.05x=19
0.2a=0.05a+3
x/x+5=2/3
3/a+1/2=11/5a
x/2=3/2x+1
1 solutions
Answer 266731 by robertb(4012) on 2010-11-22 17:23:37 (Show Source):
You can put this solution on YOUR website!x-0.05x=19 => 0.95x = 19 => x = 20.
0.2a=0.05a+3 => 0.15a = 3 => a = 20.
x/(x+5)=2/3 => 3x = 2(x+5) => 3x = 2x +10 => x = 10.
3/a+1/2=11/5a => 3/a + 0.5 = 2.2/a =>0.8/a = -0.5 => a = -1.6.
x/2=3/(2x+1) => x(2x+1) = 6 =>  => (2x - 3)(x + 2) = 0, thus x = 3/2 or x = -2.
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Mixture_Word_Problems/375068: Please help me slove this word mixture problem.
One canned juice drink is 15% orange juice, another is 5% orange juice. How many liters of each should be mixed together in order to get 10L that is 14% orange juice?
1 solutions
Answer 266730 by robertb(4012) on 2010-11-22 17:15:24 (Show Source):
You can put this solution on YOUR website!0.15x + 0.05(10 - x) = 0.14*10,
0.15x + 0.5 - 0.05x = 1.4,
0.10x = 0.9,
x = 9 liters, the amount of 15% orange juice that must be mixed with
10 - x = 1 liter of 5% orange juice.
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Triangles/374530: the question is: given a right triangle with a perimeter of 60 and an altitude to the hypotnuse with a length of 12 what is the length of each side?
i tried a lot using substitution its just too complicated i need an explanation too plz asap
1 solutions
Answer 266448 by robertb(4012) on 2010-11-21 18:59:32 (Show Source):
You can put this solution on YOUR website!A suggestion: Let x = the unknown leg, and y = the hypotenuse. Then
from the perimeter condition, x+y+12 = 60, or x+y = 48, or y = 48 - x.
From the right-triangle condition, use the Pythagorean identity :  .
Substituting, we get  . Now see if there will be any progress...
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Rectangles/374595: The length of a rectangle is 3 meters longer than the width. If the area is 36 square meters, find the rectangle's dimensions. Round to the nearest tenth of a meter.
1 solutions
Answer 266445 by robertb(4012) on 2010-11-21 18:53:13 (Show Source):
You can put this solution on YOUR website!w(w+3) = 36, or  .
then by the quadratic formula,  meters. We discard the negative value!) That's the width. The length is 4.7 + 3 = 7.7 meters.
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Triangles/374582: GIVEN 2 SIDES OF A TRIANGLE(4 AND 15) WHICH OTHER IS THE POSSIBLE SIDE LENGHT FOR THE TRIANGLE:
1, 2, 3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20
(CIRCLE THE POSSIBLE ONES)
1 solutions
Answer 266438 by robertb(4012) on 2010-11-21 18:43:26 (Show Source):
You can put this solution on YOUR website!Hmm. let's see:
If x = unknown side, then the sides of the triangle are 4, 15, and x. By a combination of the use of the triangle inequality,
4 + 15 > x, or 19 > x;
4+x > 15, or x > 11;
15 +x > 4, or x > -11. This last inequality doesn't give us any new information. But from the first two, we get
19 > x > 11. There are 7 possibilities, looking at your list. Now you know...
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Exponential-and-logarithmic-functions/374584: Find the inverse of the logarithmic function f(x)=-ln(x-2).
Steps I've done so far:
1. f(x)=-ln(x-2)
2. y=-ln(x-2)
3. x=-ln(y-2)
What is the next step? I am not sure what to do with -ln.
My instructor said the answer is: y=e^-x+2 but I don't know how he gets the -x. I know ln also stands for e.
y=-e^x+2 makes more sense to me.
1 solutions
Answer 266436 by robertb(4012) on 2010-11-21 18:36:45 (Show Source):
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Equations/374571: suppose F(X)=AX+B, G(X)=BX+A,(A AND B INTEGERS), F(1)= 8, F(G(50))-G(F(50))=28 FIND THE PRODUCT OF A AND B.
1 solutions
Answer 266434 by robertb(4012) on 2010-11-21 18:32:29 (Show Source):
You can put this solution on YOUR website!f(1) = 8 implies that a+b = 8.
f(g(50)) - g(f(50)) = f(50b +a) - g(50a+b) =  .
From the very first equation, a+b-1 = 7, so that after substitution into the last equation above, (a-b)*7 = 28, or a-b = 4. So
a-b = 4, and
a+b = 8.
It follows that 2a = 12, or a = 6, by elimination. Then b = 2. Therefore a*b = 12.
BTW, just replace a by A, and b by B. :D
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Equations/374105: Translate the following statement into an algebraic equation. Let x represent the number: 6 times a number is 14 more than that number
1 solutions
Answer 266348 by robertb(4012) on 2010-11-21 02:46:14 (Show Source):
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testmodule/374060: Find the equation of the bisector of the acute angles and also the equation of the bisector of the obtuse angles formed by the line x+y =2 and x + 2y = 3.
1 solutions
Answer 266347 by robertb(4012) on 2010-11-21 02:42:36 (Show Source):
You can put this solution on YOUR website!Let (x,y) be a point in Quadrant 4 that is located in the angle bisector of the acute angle between the two lines. We use the distance formula between a point and a line: d = |Ax + By + C|/  .
Then the point (x,y)is BELOW the line x + 2y = 3, so its distance from the said line is  .
The point (x,y)is ABOVE the line x + y = 2, so its distance from the said line is  .
Hence  ;
 . This the equation of the angle bisector of the ACUTE angle of intersection.
The arguments for the equation of the angle bisector of the OBTUSE angle of intersection run along the same lines. (But choose (x,y) now to be in Q1, and such point will be ABOVE both lines, so use +'s in place of the absolute value bars.)
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Triangles/374219: In an equilateral triangle, if the lengths of the three sides are 5x − 2, 6x − 10, and 4x + c, what are the values of x and c?
1 solutions
Answer 266343 by robertb(4012) on 2010-11-21 02:09:31 (Show Source):
You can put this solution on YOUR website!5x- 2 = 6x-10 = 4x+c.
Equate the 1st and the 2nd expressions: 5x - 2 = 6x-10, or -2 + 10 = 6x-5x, or x = 8. Equate the 2nd and the 3rd expressions : 6x-10 = 4x+c, or 2x - 10= c, or c = 2*8-10 = 16-10 = 6.
Therefore x = 8, and c = 6.
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Rectangles/374221: The width of a rectangular picture is one-half the length. The perimeter of the rectangle is 72 inches. Find the length of the picture.
1 solutions
Answer 266342 by robertb(4012) on 2010-11-21 02:04:38 (Show Source):
You can put this solution on YOUR website!l = length, w = l/2. Then PERIMETER = 2l + 2(l/2) = 72.
2l + l = 72, or 3l = 72, or l = 24 inches, the length of the rectangular picture, and w = 24/2 = 12 inches, the width of the picture.
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Numbers_Word_Problems/374252: Find how many quarts of 4% butterfat milk and 1% butterfat milk should be mixed to yield 60 quarts of 2% butterfat milk.
1 solutions
Answer 266341 by robertb(4012) on 2010-11-21 01:59:09 (Show Source):
You can put this solution on YOUR website!0.04x + 0.01(60-x) = 0.02*60
0.04x + 0.6 - 0.01x = 1.2,
0.03x = 0.6,
x = 20 quarts, the amount of 4% butterfat milk, and
60 - 20 = 40 quarts, the amount of 2% butterfat milk.
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logarithm/374248: Solve the logarithmic equation algebraically. Approximate the result to three decimal places. (If there is no solution, enter NO SOLUTION.) ln x + ln(x + 1) = 2
1 solutions
Answer 266340 by robertb(4012) on 2010-11-21 01:48:19 (Show Source):
You can put this solution on YOUR website!The logarithmic equation can be reduced to  . Using the quadratic formula, we get  . Only the value  will satisfy the original equation, and so this is the final answer. And that my STUDENT, is how it's done...
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