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checkley71 answered: 8399 problems
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Functions/113574: Can someone help me with this? I am really confused with the answers I keep coming up with.
If y= (sqrt of x) - 2, fill in the following table for x = 0, 1, 2, 3, 4. Round to three decimal places where necessary.
Thank you in adveance for your help.
1 solutions

Answer 82680 by checkley71(8403) About Me  on 2007-11-30 21:23:01 (Show Source):
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y=sqrtx-2
y=sqrt0-2
y=-2 answer.
y=sqrt1-2
y=1-2
y=-1 answer.
y=sqrt2-2
y=1.414-2
y=.586 answer.
y=sqrt3-2
y=1.732-2
y=-.268 answer
y=sqrt4-2
y=2-2
y=0 answer.


Polynomials-and-rational-expressions/113585: This question is from textbook Introductory Algebra

-x*x-4*x+x*x*x*x-4
1 solutions

Answer 82678 by checkley71(8403) About Me  on 2007-11-30 21:18:40 (Show Source):
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-x*x-4*x+x*x*x*x-4
-x^2-4x+x^4-4
x^4-x^2-4x-4 answer.


Linear-equations/113614: 6x+y=12

1 solutions

Answer 82677 by checkley71(8403) About Me  on 2007-11-30 21:15:50 (Show Source):
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IF THIS IS A LINE EQUATION THEN:
Y=-6X+12
+graph%28+300%2C+200%2C+-6%2C+5%2C+-10%2C+15%2C+y+=+-6x+%2B12%29+ (graph 300x200 pixels, x from -6 to 5, y from -10 to 15, y = -6x +12).


Polynomials-and-rational-expressions/113613: Give a ratio comparing the first quantity to the second, then as a percent.
2 hours for homework and 30 minutes for pracricing
Thank you!
1 solutions

Answer 82676 by checkley71(8403) About Me  on 2007-11-30 21:13:23 (Show Source):
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2:0.5 IS THE RATIO.
2/0.5=4 OR 400% IS THE PERCENTAGE.


Radicals/113599: 3y squard=192
1 solutions

Answer 82675 by checkley71(8403) About Me  on 2007-11-30 21:09:25 (Show Source):
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3Y^2=192
Y^2=192/3
Y^2=64
Y=SQRT64
Y=8 ANSWER.
PROOF
3*8^2=192
3*64=192
192=192


Quadratic_Equations/113601:
The hypotenuse of a right triangle is 2.4 units long. The longer leg is 1.4 units longer than the shorter leg. Find the lengths of the sides of the triangle.

1 solutions

Answer 82674 by checkley71(8403) About Me  on 2007-11-30 21:06:29 (Show Source):
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2.4^2=X^2+(X+1.4)^2
5.76=X^2+X^2+2.8X+1.96
2X^2+2.8X+1.96-5.76=0
2X^2+2.8X-3.8=0
2(X^2+1.4X-1.9)=0
USING THE QUADRATIC EQUATION WE GET:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
X=(-1.4+-SQRT[1.4^2-4*1*-1.9])/2*1
X=(-1.4+-SQRT1.96+7.6])/2
X=(-1.4+-SQRT9.56)/2
X=(-1.4+-3.092)/2
X=(-1.4+3.092)/2
X=1.692/2
X=.846 ANSWER FOR THE SHORTER SIDE.
.846+1.4=2.246 ANSWER FOR THE LONGER SIDE.
PROOF
2.4^2=.846^2+2.246^2
5.76=.716+5.044
5.76=5.76



Quadratic_Equations/113605: Write the equation x(x - 7) + 10 = 0 in quadratic form and then solve it by factoring.
1 solutions

Answer 82670 by checkley71(8403) About Me  on 2007-11-30 20:51:23 (Show Source):
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X(X-7)+10=0
X^2-7X+10=0
(X-5)(X-2)=0
X-5=0
X=5 ANSWER.
X-2=0
X=2 ANSWER.


Quadratic_Equations/113606: Solve the equation.

y 2 - 15 y + 44 = 0
1 solutions

Answer 82667 by checkley71(8403) About Me  on 2007-11-30 20:49:36 (Show Source):
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Y^2-15Y+44=0
(Y-11)(Y-4)=0
Y-11=0
Y=11 ANSWER.
Y-4=0
Y=4 ANSWER.


Quadratic_Equations/113608: What values of b will make x^2 + bx + 2/5 a perfect square trinomial ?
1 solutions

Answer 82666 by checkley71(8403) About Me  on 2007-11-30 20:47:55 (Show Source):
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X^2+BX+2/5
X^2+2(SQRT2/5)X+2/5 ANSWER.
OR X^2+2(SQRT0.4)+0.4 ANSWER.
OR X^2+1.2649X+0.4 ANSWER.


Quadratic_Equations/113602: Use the quadratic formula to solve the equation
-
3x^2-40x=59
1 solutions

Answer 82662 by checkley71(8403) About Me  on 2007-11-30 20:40:26 (Show Source):
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3X^2-40X-59=0
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
X=(40+-SQRT[-40^2-4*3*-59])/2*3
X=(40+-SQRT[1600+708])/6
X=(40+-SQRT2308)/6
X=(40+-48.04)/6
X=(40+48.04)/6
X=88.04/6
X=14.67 ANSWER.
X=(40-48.04)/6
X=-8.04/6
X=-1.34 ANSWER.


Polynomials-and-rational-expressions/113592: Multiply, using the vertical method.

(2r - 3s)(4r squared + 6rs + 9s squared)
1 solutions

Answer 82661 by checkley71(8403) About Me  on 2007-11-30 20:34:11 (Show Source):
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2R-3S
4R^2+6RS+9S^2
-----------------------------------
8R^3-12R^2S+12R^2S-18RS^2+18RS^2-27S^3
8R^3-27S^3 ANSWER.


Radicals/113593: I need help with this word problem please.

The volume of a cube is given by V=s^3, where s is the length of a side. Find the length of a side of a cube if the volume is 500 cm^3. Round answer to three decimal places.

1 solutions

Answer 82659 by checkley71(8403) About Me  on 2007-11-30 20:28:33 (Show Source):
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V=S^3
500=S^3
S=CUBEROOT500
S=7.937 ANSWER.
PROOF
7.937*7.937*7.937~500


Equations/113597:
2ax-5x=2
solve for x
thank you
1 solutions

Answer 82658 by checkley71(8403) About Me  on 2007-11-30 20:24:13 (Show Source):
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2AX-5X=2 FACTOR OUT THE COMMON X TERM.
X(2A-5)=2 DIVIDE BOTH SIDES BY(2A=5)
X=2/(2A-5) ANSWER.


Square-cubic-other-roots/113596: can some one help me solve this problem.
^3 square root x-4=2
thank you.
1 solutions

Answer 82657 by checkley71(8403) About Me  on 2007-11-30 20:21:24 (Show Source):
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IT APPEARS THAT SOMETHING IS MISSING BEFORE THE CUBE SIGN (^3)!


Square-cubic-other-roots/113595: CAN SOME ONE HELP ME SOLVE THIS WORD PROBLEM.

Suppose that N= square root x +3 models the number of cases of an infection, in millions, of a disease x years from now.
a. approximately how many cases of the infection will there be in 9 years from now?
b. in approximatetly how many years will there be in 5 million cases?
1 solutions

Answer 82656 by checkley71(8403) About Me  on 2007-11-30 20:19:41 (Show Source):
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N=SQRT(X+3)
N=SQRT(9+3)
N=SQRT12
N=3.464 MILLION CASES IN 9 YEARS.
-----------------------------------------
5=SQRT(X+3) NOW SQUARE BOTH SIDES OF THE EQUATION:
25=X+3
X=25-3
X=22 YEARS THERE WILL BE 5,000 CASES.


Triangles/113469: This question is from textbook
Find the coordinates of the midpoint of the segment with endpoints (-8, -3) and (1, 6).
1 solutions

Answer 82576 by checkley71(8403) About Me  on 2007-11-30 11:03:04 (Show Source):
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THE X DISTANCE=(1+8)/2=4.5 OR -8+4.5=-3.5
THE Y DISTANCE=(6+3)/2=4.5 OR 6-4.5=1.5
THEREFORE THE MID POINT IS (-3.5,1.5)
THE PROOF IS IN THE GRAPHING OF THESE 2 POINTS, DRAWING THE LINE & THEN PLOT THE MID POINT.


Polynomials-and-rational-expressions/113511: Solve the equation



A = 1/2(b + B) for B

Totally lost on this problem. Can someone help me please.
1 solutions

Answer 82573 by checkley71(8403) About Me  on 2007-11-30 10:54:15 (Show Source):
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A=1/2(b+B)
A=(b+B)/2 CROSS MULTIPLY.
2A=b+B SUBTRACT b FROM BOTH SIDES.
B=2A-b ANSWER.


Equations/113513: How do I solve the equation 5X=72. If needed I can round to the nearest three decimal places.
NOTE: the (x) following the 5 should be written as expanded notation. I just do not know how to write it like that on the computer.
1 solutions

Answer 82572 by checkley71(8403) About Me  on 2007-11-30 10:49:11 (Show Source):
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5^X=72
USING THE TRIAL & ERROR METHOD I GET:
5^2.657242=72
71.99999268~72


Linear-equations/113474: In which quadrant does the following point lie?
(-3 , 5)
Find the slope of the line through (3,-4) and (1,2)
1 solutions

Answer 82571 by checkley71(8403) About Me  on 2007-11-30 10:34:58 (Show Source):
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(-3,5) LIES IN THE SECOND QUADRANT.
------------------------------------------
SLOPE=(Y2-Y1)/(X2-X1)
(2+4)/(1-3)
6/-2=-3 ANSWER FOR THE SLOPE OF A LINE THROUGH (3,-4) & (1,2)


Money_Word_Problems/113480: Please help.
A coffee merchant has coffee beans that sell for $9 per pound and $12 per pound.
The two types are to be mixed to create 100 lb of a mixture that will sell for $11.25 per pound.
How much of each type of bean should be used in the mixture?
Please show the equations used for the solution.
Thanks
JMS

1 solutions

Answer 82570 by checkley71(8403) About Me  on 2007-11-30 10:30:32 (Show Source):
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9X+12(100-X)=100*11.25
9X+1200-12X=1125
-3X=1125-1200
-3X=-75
X=-75/-3
X=25 ANSWER. FOR THE POUNDS OF $9 COFFEE USED.
100-25=75 FOR THE POUNDS OF $12 COFFEE USED.
PROOF
9*25+12*75=100*11.25
225+900=1125
1125=1125



Rectangles/113481: Please help.


The length of a rectangle is 2 in. more than twice its width.
If the perimeter of the rectangle is 34 in., find the dimensions of the rectangle.
Please show equations used for the solution.
Thanks
JMS
1 solutions

Answer 82569 by checkley71(8403) About Me  on 2007-11-30 10:25:16 (Show Source):
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L=2W+2
PERIMETER=2*L+2W
34=2(2W+2)+2W
34=4W+4+2W
34=6W+4
6W=34-4
6W=30
W=30/6
W=5 IN. ANSWER.
L=2*5+2
L=10+2
L=12 IN. ANSWER.
PROOF:
34=2*5+2*12
34=10+24
34=34


Polynomials-and-rational-expressions/113494: This question is from textbook Glencoe Mathematics Algebra 1








54x^2y + 63xy + 9y
1 solutions

Answer 82568 by checkley71(8403) About Me  on 2007-11-30 10:19:48 (Show Source):
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IF YOU'RE LOOKING FOR THE FACTORS OF THIS EQUATION THEN:
54X^2Y+63XY+9Y
9Y(6X^2+7X+1)
9Y(6X+1)(X+1)


Linear_Equations_And_Systems_Word_Problems/113508: A father is 7 times as old as his son.2 years ago the father was 13 times as old as his son, how old are they now.
1 solutions

Answer 82567 by checkley71(8403) About Me  on 2007-11-30 10:15:43 (Show Source):
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DAD=7X WHEN THE SON'S AGE IS X NOW.
2 YEARS AGO THEY WERE:
DAD=(7X-2) & THE SON=(X-2)
SO WE HAVE:
7X-2=13(X-2)
7X-2=13X-26
7X-13X=-26+2
-6X=-24
X=-24/-6
X=4 THE AGE OF THE SON NOW.
THUS THE DAD=7*4=28 YEARS OLD NOW.
PROOF:
7*4-2=13(4-2)
28-2=13*2
26=26


Human-and-algebraic-language/113502: A community hall has an area of 396 metres squared. A 12 metre by 16 metre rug is placed on the floor so that the width of the floor showing on the four sides is uniform. What is the distance between the rug and the wall ?
1 solutions

Answer 82564 by checkley71(8403) About Me  on 2007-11-30 10:08:11 (Show Source):
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396=(12+2X)(16+2X)
X BEING THE SPACE BETWEEN THE RUG & THE WALL.
IT HELPS TO DRAW A DIAGRAM TO CAPTURE THE PROGRAM PICTORALLY.
396=192+32X+24X+4X^2
4X^2+56X+192-396=0
4X^2+56X-204=0
4(X^2+14X-51)=0
4(X-3)(X+17)=0
X-3=0
X=3 METERS IS THE SPACE BETWEEN THE RUG & THE WALL.


Numbers_Word_Problems/113504: This question is from textbook Arithmetic and algebra again
The sum of two numbers is 22. Five times one number is equal to 6 times the second number. Find the numbers.
x + y = 22
5x = 6y
I believe these are the correct equations, but I am drawing blanks. I know the answer is x=12, y=10 just from the second equation, but I cannot do it algebraically.
1 solutions

Answer 82563 by checkley71(8403) About Me  on 2007-11-30 10:01:17 (Show Source):
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X+Y=22 OR X=22-Y
5X=6Y
NOW REPLACE X IN THIS EQUATION WITH (22-Y) & SOLVE FOR Y;
5(22-Y)=6Y
110-5Y=6Y
11Y=110
Y=10 ANSWER.
X+10=22
X=22-10
X=12 ANSWER.


Linear-systems/113371: write the point-slope form of the equation of the line that passes through the two points


(4, -2), (-9, 5)
Thanks for help
1 solutions

Answer 82500 by checkley71(8403) About Me  on 2007-11-29 19:10:12 (Show Source):
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FIRST YOU NEED TO FIND THE SLOPE (Y2-Y1)/(X2-X1)
(5+2)/(-9-4)=7/-13 OR -7/13
Y=mX+b.
NOW SUPSTITUTE ONE SET OF X,Y POINTS & THE SLOPE (m) & SOLVE FOR (b) THE Y INTERCEPT.
-2=-7/13*4+b
-2=-28/13+b
b=-2+28/13
b=(-26+28)/13
b=2/13 ANSER FOR THE Y INTERCEPT.
THUS WE HAVE THE FOLLOWING LINE EQUATION:
Y=-7X/13+2/13


Equations/113341: Solve the inequality

53. 1/2m + 1 > 7/4
Any help with this equation wuld be Greatly appreciated.
1 solutions

Answer 82498 by checkley71(8403) About Me  on 2007-11-29 18:42:10 (Show Source):
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M/2+1>7/4
M/2>7/4-1
M/2>(7-4)/4
M/2>3/4
M>(3/4)*2
M>6/4
M>1.5 ANSWER.
LET M=1.6
PROOF
1.6/2+1>7/4
.8+1>7/4
1.8>1.75


Numbers_Word_Problems/113366: Find three positive consecutive even integers such that the product of the first and second is 8 more than 38 times the third.
1 solutions

Answer 82497 by checkley71(8403) About Me  on 2007-11-29 18:37:19 (Show Source):
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X, X+2, X+4 ARE THE 3 POSITIVE CONSECUTIVE INTEGERS.
X(X+2)=8+38(X+4)
X^2+2X=8+38X+152
X^2+2X-38X-8-152=0
X^2-36X-160=0
(X-40)(X+4)=0
X-40=0
X=40 ANSWER FOR THE FIRST INTEGER.
40+2=42 FOR THE SECOND INTEGER.
40+4=44 FOR THE THIRD INTEGER.
PROOF
40*42=8+38*44
1680=8+1672
1680=1680


Linear-systems/113372: write the point slope form of the equation of the line that passes through the point and has the given slope, then rewrite the equation in slope-intercept form
(-2, 4), m = 3
Thanks for help
1 solutions

Answer 82496 by checkley71(8403) About Me  on 2007-11-29 18:29:37 (Show Source):
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Y=mX+b WHERE m=SLOPE & b=Y INTERCEPT.
NOW SUBSTITUTE THE X&Y VALUES & THE SLOPE (m) & SOLVER FOR b.
4=3*-2+b
4=-6+B
b=4+6
b=10 THUS WE HAVE THE FOLLOWING EQUATION.
Y=3X+10


Mixture_Word_Problems/113369:
1.If you add pure alcohol to a 15%alcohol solution, what percent alcohol are you adding, and how do you represent the percentage in decimal form?

2. If 4 gallons of alcohol is added to 2 gallons of a 15% percent solution, what percentage of alcohol is in the mixture?
1 solutions

Answer 82494 by checkley71(8403) About Me  on 2007-11-29 18:26:09 (Show Source):
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.15X+Y WHERE X IS THE AMOUNT OF 15% ALCOHOL & Y= THE AMOUNT OF 100% ALCOHOL.
.15*2+4=Z*6 HERE THE Z IS THE PERCENT OF MIXED ALCOHOL CONTAINED IN THE 6 GALLONS.
.3+4=6Z
6Z=4.3
Z=4.3/6
Z=.717 OR 71.7% ALCOHOL.


Equations/113364: This question is from textbook Advanced Algebra


A=P+Prt
Solve for P
Solve for r
1 solutions

Answer 82491 by checkley71(8403) About Me  on 2007-11-29 18:06:58 (Show Source):
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A=P+PRT
A=P(1+RT)
P=A/(1+RT) ANSWER.
--------------------------
A-P=PRT
R=(A-P)/PT ANSWER.