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Graphs/64698: This question is from textbook An Incremental Development
Find the equation of the line that passes through (3,-5) and is perpendicular to the line that passes through (7,-5) and (-2,-4)
1 solutions

Answer 45255 by checkley71(8403) About Me  on 2006-12-11 18:14:39 (Show Source):
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FIRST WE FIND THE SLOPE OF THE LINE THROUGH THE 2 POINTS THUS
(Y2-Y1)/(X2-X1)
(-4+5)/(-2-7)
1/-9 IS THE SLOPE OF THE LINE THROUGH ((7,-5)(-2,-4)
NOW TO IDENTIFY A LINE PERPENDICULAR TO THIS LINE IT HAS TO HAVE A SLOPE OF A NEGATIVE RECIPRICAL OF THIS SLOPE. THUS THE SL;OPE OF A LINE PERPENDICULAR TO THIS LINE THROUGH (3,-5) HAS A SLOPE OF 9. NOW WE SUBSTITUTE THESE X&Y POINTS IN THE FORMULA USING THE NEW SLOPE WE GET
-5=9*3+b
-5=27+b
b=-5-27
b=-32 THUS THUIS EQUATION IS
Y=9X-32


Polynomials-and-rational-expressions/64701: This question is from textbook algebra for college students
Hello,
with the quadratic formula, how would you solve:
x^2 - 3x - 10 = 0
Thank you.
1 solutions

Answer 45254 by checkley71(8403) About Me  on 2006-12-11 18:07:24 (Show Source):
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X^2-3X-10=0
THE QUADRATIC EQUATION IS X=(-B+-SQRT[B^2-4AC])/2A THUS WE HAVE
X=(3+-SQRT[-3^2-4*1*-10])/2*1
X=(3+-SQRT[9+40])/2
X=3+-SQRT49)/2
X=(3+-7)/2
X=(3+7)/2
X=10/2
X=5 SOLUTION
X=(3-7)/2
X=-4/2
X=-2 SOLUTION


Polynomials-and-rational-expressions/64722: the perimeter of a rectangle is 52 feet ans its width is 6 less then is lenght. Find the length and width of the rectangle.

1 solutions

Answer 45252 by checkley71(8403) About Me  on 2006-12-11 18:00:58 (Show Source):
You can put this solution on YOUR website!
W=L-6 THEN
2*L+2(L-6)=52
2L+2L-12=52
4L=64
L=64/4
L=16 SOLUTION FOR THE LENGTH THEN
W=16-6
W=10 SOLUTION
PROOF
2*16=2*10=52
32+20=52
52=52


Travel_Word_Problems/64718: This question is from textbook algebra 1
An airline starts off on a trip with all engines running. It is going at a rate of 900 km per hour, after x hours it shuts down one engine and reduces its speed to 700 km per hour. The trip is a total of 3 hours long
How lonng should the pilot fly before shutting down one engine in order to go a total distance of 2352 in 3 hours.
1 solutions

Answer 45246 by checkley71(8403) About Me  on 2006-12-11 17:29:12 (Show Source):
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900T+700(3-T)=2352
900T+2100-700T=2352
200T=2352-2100
200T=252
T=252/200
T=1.26 HOURS @ 900 MPH BEFORE SHUTTING DOWN THE ENGINE
PROOF
900*1.26+700(3-1.26)=2352
1134+700*1.74=2352
1134+1218=2352
2352=2352


Polynomials-and-rational-expressions/64700: This question is from textbook An Incremental Development
evaluate
x^2 + xy^3 + xy if x = - 1/3 and y = -1/2
1 solutions

Answer 45245 by checkley71(8403) About Me  on 2006-12-11 17:21:46 (Show Source):
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x^2+xy^3+xy
(-1/3)^2+(-1/3*-1/2^3)+(-1/3*-1/2)
1/9+(-1/3*-1/8)+(1/6)
1/9+(1/24)+1/6
1/9+1/24+1/6 now we need to find a common denominator for these three terms so we can add them
factors of 9 =3*3
factors of 6=3*2
factors of 24=2*2*2*3 combining common factors (using triplicate & duplicate factors only once) we have 3*3*2*2*2=72
(8+3+12)/72
23/72 solution


Polynomials-and-rational-expressions/64702: This question is from textbook algebra for college students
Hello,
with the quadratic formula, how would you solve:
6x^2 - 7x = 3
thank you.
1 solutions

Answer 45244 by checkley71(8403) About Me  on 2006-12-11 17:08:19 (Show Source):
You can put this solution on YOUR website!
6x^2-7x=3
6x^2-7x-3=0
the quadratic equation is
x=(-b+-sqrt[b^2-4ac])/2a thus we have
x=(7+-sqrt[-7^2-4*6*-3])/2*6
x=(7+-sqrt[49+72])/12
x=(7+-sqrt[121])/12
x=(7+-11)/12
x=(7+11)/12
x=18/12
x=1.5 solution
x=(7-11)/12
x=-4/12
x=-1/3 solution


Complex_Numbers/64608: Solve in the complex number system.
8x^3 + 27 = 0
1 solutions

Answer 45210 by checkley71(8403) About Me  on 2006-12-11 08:50:13 (Show Source):
You can put this solution on YOUR website!
8x^3+27=0
8x^3=-27
x^3=-(27/8)
x=-3/2
proof
8(-3/2)^3=27=0
8(-27/8)+27=0
-27+27=0
0=0


Expressions-with-variables/64522: Solve for the variable: 2x2^ + 8x = 0
a) 0 or 4
b) 0 only
c) 4 only
d) 0 or -4
e) None of these
1 solutions

Answer 45178 by checkley71(8403) About Me  on 2006-12-10 20:08:07 (Show Source):
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2X^2+8X=0
2X(X+4)=0
2X=0
X=0 SOLUTION
X+4=0
X=-4 SOLUTION
SOLUTIONS ARE (0 & -4)


Functions/64535: please help me Perform the indicated operations
3. 2y – 3y[4 – 2(y – 1)]
4. (4x – 3y)2

1 solutions

Answer 45175 by checkley71(8403) About Me  on 2006-12-10 20:03:39 (Show Source):
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2Y-3Y[4-2(Y-1)]
2Y-3Y[4-2Y+2]
2Y-3Y[-2Y+6]
2Y+6Y^2-18Y
6Y^2+2Y-18Y
6Y^2-16Y
2Y(3Y-8)


Equations/64541: This question is from textbook
3x-x+8=16

1 solutions

Answer 45172 by checkley71(8403) About Me  on 2006-12-10 19:51:11 (Show Source):
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3X-X+8=16
2X=16-8
2X=8
X=8/2
X=4 SOLUTION
PROOF
3^4-4+8=16
12-4+8=16
16=16


Linear_Algebra/64546: (5a-2)^2-a=0
1 solutions

Answer 45171 by checkley71(8403) About Me  on 2006-12-10 19:47:53 (Show Source):
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(5A-2)^2-A=0
25A^2-20A+4-A=0
25A^2-21A+4=0
USING THE QUADRATIC EQUATION WE GET
X=(-B+-SQRT[B^2-4AC])/2A
X=(21+-SQRT[441-4*25*4])/2*25
X=(21+-SQRT[441-400])/50
X=(21+-SQRT41])/50
X=(21+-6.4)/50
X=(21+6.4)/50
X=27.4/50
X=.548 SOLUTION
X=(21-6.4)/50
X=14.6/50
X=.292 SOLUTION



Linear_Algebra/64552: Solve for x: [6x-5]-3=-2
1 solutions

Answer 45168 by checkley71(8403) About Me  on 2006-12-10 19:38:32 (Show Source):
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[6x-2]-3=-2
6x-2-3=-2
6x=-2+2+3
6x=3
x=3/6
x=1/2


Linear-equations/64554: Find the equation of the line through (-1,2) that is perpendicular to 3x-y=4
1 solutions

Answer 45167 by checkley71(8403) About Me  on 2006-12-10 19:35:59 (Show Source):
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3x-y=4
-y=-3x+4
y=3x-4 thus the slope of this line is 3. A line perpendicular to this one has a slope of -1/3. Using this slope & the two points we have the line formula of--
y=mx+b where m=slope & b=y intercept.
2=(-1/3)*-1+b
2=1/3+b
b=2-1/3
b=1 2/3 or 5/3
Thus this line is y=-1/3x+5/3


percentage/64557: This question is from textbook Algebra 1
Hiriko invested $11,700,part at 5% interest and the balance at 7% interest.If her annaul earnings from both investments is $733,how much is invested at each rate?
1 solutions

Answer 45165 by checkley71(8403) About Me  on 2006-12-10 19:26:30 (Show Source):
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.07x+.05(11700-x)=733
.07x+585-.05x=733
.02x=733-585
.02x=148
x=148/.02
x=7400 amount invested @ 7%.
then the remainder is (11700-7400=4300) or 4300 is invested @ 5%
proof
.07*7400+.05*4300=733
518+215=733
733=733


Functions/64478: will you help with a word problem?

My Phone Co, Inc. uses the following price schedule: x < 200 minutes, $.25 per minute; between 201 and 500 minutes, $.15 per minute; Over 501 minutes, $.10 per minute.
How much does 480 minutes cost?

1 solutions

Answer 45139 by checkley71(8403) About Me  on 2006-12-10 15:20:33 (Show Source):
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480*.15=$72.00 FOR 480 MINUTES @ $.15 PER MINUTE.


Functions/64479: I really need help on this
Find the equation of the line in slope intercept form given the following:
19.) m = 5 and point (3, -10)
20.) The line runs through (2, 3) and (-3, 7)

1 solutions

Answer 45138 by checkley71(8403) About Me  on 2006-12-10 15:17:40 (Show Source):
You can put this solution on YOUR website!
Y=mX+b
-10=5*3+b
-10=15+b
b=-1)-15
b=-25 THEN THE EQUATION IS
Y=5X-25
-----------------------------------------------------
TO FIND THE SLOPE(m) WE MAKE A FRACTION (Y2-Y1/(X20-X1)
SLOPE=(7-3)/(-3-2)
SLOPE=4/-5
SLOPE=-4/5 NOW WE FIND THE Y INTERCEPT(b) BY USING ONE SET OF POINTS FOR X & Y
3=-4/5*2+b
b=3+4/5
b=19/5 THUS WE HAVE
Y=-4/5X+19/5 FOR THE LINE PASSING THROUGH THESE TWO POINTS.


Numbers_Word_Problems/64506: This question is from textbook An Incremental Development
Maria finished with 180 percent of what she started with. If she finished with 7200, how many did she start with?
1 solutions

Answer 45137 by checkley71(8403) About Me  on 2006-12-10 15:10:08 (Show Source):
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1.8x=7200
x=7200/1.8
x=4000


Travel_Word_Problems/64507: This question is from textbook An Incremental Development
Jolene and Samantha began a trip from the same place at the same time. If Jolene's speed was 40mph and Samantha's speed was 50mph, how many hours will it take for Samantha to get 25 miles ahead?
1 solutions

Answer 45136 by checkley71(8403) About Me  on 2006-12-10 15:07:48 (Show Source):
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40t+25=50t
-10t=-25
10t=24
t=25/10
t=2.5 hours


Square-cubic-other-roots/64517: Combine and Simplify: (square root of)160 - (square root of)490
a) -(square root of)320
b) -3(square root of)10
c) -30
d) -3
e) None of these
1 solutions

Answer 45135 by checkley71(8403) About Me  on 2006-12-10 15:04:58 (Show Source):
You can put this solution on YOUR website!
sqrt160-sqrt490
4sqrt10-7sqrt10
-3sqrt10
answer B)-3sqrt10


Expressions-with-variables/64524: REAL WORLD PROBLEM!!!
Source: http://verizonmath.blogspot.com/
Verizon Wireless charges for data use. Their rate for this data use is .002 cents per kilobyte. If George uses 35,893 kilobytes, What does he owe in dollars?
1 solutions

Answer 45134 by checkley71(8403) About Me  on 2006-12-10 14:59:40 (Show Source):
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.002*35,893=$71.786


Unit_Conversion_Word_Problems/64529: A rectangle has sides of 3x – 4 and 7x + 10. Find the expression that represents its perimeter
1 solutions

Answer 45133 by checkley71(8403) About Me  on 2006-12-10 14:57:34 (Show Source):
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2(3x-4)+2(7x+10)=6x-8+14x+20=20x+12=4(5x+3)


Unit_Conversion_Word_Problems/64528: If a 4.4-pound bag of dog food costs $3.52, what is the cost per pound?
1 solutions

Answer 45132 by checkley71(8403) About Me  on 2006-12-10 14:48:41 (Show Source):
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3.52/4.4=$.60 per pound.


Equations/64432: This question is from textbook Algebra
Simplify
3 4 5
-- + --- - ---
n n n
1 solutions

Answer 45097 by checkley71(8403) About Me  on 2006-12-09 22:16:57 (Show Source):
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3/N+4/N-5/N
(3+4-5)/N
2/N


Equations/64431: This question is from textbook Algebra
Multiply express product in simplest form
2 9
-- X ---
15 16
1 solutions

Answer 45096 by checkley71(8403) About Me  on 2006-12-09 22:15:16 (Show Source):
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2/15*9/16
18/240
3/40


Functions/64471: I need your help
Given f(x) = x^2 + 5 and g(x) = 5x – 2, solve the following functions:
15. f(6)
16. g(-2)

1 solutions

Answer 45095 by checkley71(8403) About Me  on 2006-12-09 22:12:19 (Show Source):
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F(X)=X^2+5
F(6)=6^2+5
F(6)=36+5
F(6)=41
------------------------------------
G(X)=5X-2
G(-2)=5*-2-2
G(-2)=-10-2
G(-2)=-12


Linear-equations/64461: To find an equation of a line given the slope and one point on the line
m = 0; (-5, 3)
4

1 solutions

Answer 45092 by checkley71(8403) About Me  on 2006-12-09 22:08:57 (Show Source):
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Y=mX+b
3=0*-5+b
3=b THEN THE EQUATION FOR THIS LINE IS
Y=3


Linear-equations/64453: write an equation that contains the points (2,-1) and (-5,-1)?
1 solutions

Answer 45075 by checkley71(8403) About Me  on 2006-12-09 17:46:01 (Show Source):
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FIRST WE FIND THE SLOPE OF THIS LINE WHICH IS (Y2-Y1)/(X2-X1)
(-1+1)/-5-7)=0/-12=0 THEREFORE THIS A HORIZONTAL LINE WITH SLOPE OF 0 & PASSES THROUGH Y=-1.
THEREFORE THE LINE EQUATION Y=mX+b (m=SLOPE, b=Y INERCEPT)
BECOMES Y=-1


Polynomials-and-rational-expressions/64396: Factor completely. x^3 + 8x^2 + 15x

1 solutions

Answer 45053 by checkley71(8403) About Me  on 2006-12-09 11:13:34 (Show Source):
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X^3+8X^2+15X
X(X^2+8X+15)
X(X+5)(X+3)


Linear-systems/64402: This question is from textbook McDougal Littell
2876question #42 says you are selling tickets for a high school play students tickets cost 4$ and general admission cost$6. you sell 525 tickets and collect $2876 how many of each type of ticket did you sell? so far the only thing i get is that one of the equatons is i think 4x+6y=525 but i don't know how to get the other one,? help?
1 solutions

Answer 45052 by checkley71(8403) About Me  on 2006-12-09 11:11:49 (Show Source):
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S+G=525 STUDENT + GENERAL ADMISSION TICKETS SOLD
4S+6G=2876 AMOUNT OF MONEY COLLECTED FOR SELLING STUDENT TICKETS FOR $4 & GENERAL ADMISSION FOR $6.
THEN S=525-G NOW SUBSTITUTE (525-G) FOR S IN THE OTHER EQUATION WE GET
4(525-G)+6G=2876
2100-4G+6G=2876
2G=2876-2100
2G=776
G=776/2
G=388 THE NUMBER OF GENERAL ADMISSION TICKETS SOLD. THEN
525-388=137 NUMBER OF STUDENT TICKETS SOLD.
PROOF
4*137+6*388=2876
548+2328=2876
2876=2876


Polynomials-and-rational-expressions/64405: Factor completely. 5x^2 + 35x + 60
1 solutions

Answer 45050 by checkley71(8403) About Me  on 2006-12-09 11:01:59 (Show Source):
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5X^2+35X+60
5(X^2+7X+12)
5(X+4)(X+3)


Polynomials-and-rational-expressions/64409: Factor completely. ax – ay + x^2 – xy
1 solutions

Answer 45049 by checkley71(8403) About Me  on 2006-12-09 10:59:48 (Show Source):
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AX-AY+X^2-XY
A(X-Y)+X(X-Y)
(A+X)(X-Y)