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Graphs/81901: Identify the axis of symmetry, create a suitable table of values, then sketch the graph (including the axis of symmetry).
y = –x^2 + 3x – 3
thank you
1 solutions
Answer 58686 by checkley75(3666)   on 2007-05-13 19:49:07 (Show Source):
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Linear-equations/81871: What's the linear equation of these ordered pairs?
(6,-2) (-9,3) (-6,2)
1 solutions
Answer 58684 by checkley75(3666) on 2007-05-13 19:40:13 (Show Source):
You can put this solution on YOUR website!SLOPE=(3+2)/(-9-6)
SLOPE=5/-15
SLOPE=-1/3 NOW SUBSTITUTE ONE SET OF (X,Y) POINTS IN THE LINE EQUATION & SOLVE FOR THE Y INTERCEPT (b)
Y=mX+b
-2=-1/3*6+b
-2=-2+b
b=-2+2
b=0 SO THE LINE EQUATION IS Y=-1/3X
 (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, y = -x/3).
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Quadratic_Equations/81717: The difference of two numbers is 47. The second is 1 less than 3 times the first. What are the two numbers?
Answer:X+Y=47, X=47-Y
Y=3X-1 NOW SUBSTITUTE (47-Y) FOR X IN THE THIS EQUATION & SOLVE FOR Y
Y=3(47-Y)-1, Y=141-3Y-1, Y+3Y=140, 4Y=140, Y=140/4, Y=35ANSWER.
X+35=47, X=47-35, X=12 ANSWER.
One number is: 12
And the other number is: 35
1 solutions
Answer 58673 by checkley75(3666) on 2007-05-13 14:45:18 (Show Source):
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Quadratic_Equations/81861: (a-2)(a+4)= 2a(a-3)
1 solutions
Answer 58671 by checkley75(3666) on 2007-05-13 14:28:23 (Show Source):
You can put this solution on YOUR website!(A-2)(A+4)=2A(A-3)
A^2+2A-8=2A^2-6A
A^2-2A^2+2A+6A-8=0
-A^2+8A-8=0
A^2-8A+8=0
USING THE QUADRATIC EQUATION WE GET:
A=(8+-SQRT[-8^2-4*1*8])/2*1
A=(8+-SQRT[64-32])/2
A=(8+-SQRT32)/2
A=(8+-5.657)/2
A=(8+5.657)/2
A=13.657/2
A=6.8285 ANSWER.
A=(8-5.657)/2
A=2.343/2
A=1.1715 ANSWER.
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Quadratic_Equations/81864: 9x^2-120x-81=0
How is this worked out?
1 solutions
Answer 58667 by checkley75(3666) on 2007-05-13 14:12:38 (Show Source):
You can put this solution on YOUR website!9X^2-120X-81=0
USING THE QUADRATIC EQUATION WE GET:
X=(120+-SQRT[-120^2-4*9*-81])/(2*9)
X=(120+-SQRT[14400+2906])/18
X=(120+-SQRT17316)/18
X=(120+-131.59)/18
X=(120+131.59)/18
X=251.59/18
X=13.977 ANSWER
X=(120-131.59)/18
X=-11.59/18
X=-.644 ANSWER.
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Linear_Equations_And_Systems_Word_Problems/81863: The sum of two numbers is 20. The difference of the two numbers is twice the smaller number. Write a system of equations that will determine the two numbers.
1 solutions
Answer 58666 by checkley75(3666) on 2007-05-13 14:04:54 (Show Source):
You can put this solution on YOUR website!X+Y=20 THIS IS THE SUM OF THE TWO NUMBERS WITH X BEING THE SMALLER NUMBER.
Y-X=2X THIS IS THE DIFFERENCE THAT IS TWICE THE SMALLER NUMBER.
YOU DON'T ASK TO SOLVE FOR THE TWO NUMBERS BUT I WILL SOLVE THEM FOR YOU.
X+Y=20 OR X=20-Y NOW SUBSTITUTE (20-Y) FOR X IN THE OTHER EQUATION THUS:
Y-(20-Y)=2(20-Y)
Y-20+Y=40-2Y
2Y+2Y=40+20
4Y=60
Y=60/4
Y=15 ANSWER.
X+15=20
X=20-15
X=5 ANSWER.
PROOF
15-5=2*5
10=10
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Quadratic_Equations/81641: Lane invested $14,000, part at 15% and part at 2%. If the total interest at the end of the year is $1,060, how much did she invest at 15%?
1 solutions
Answer 58542 by checkley75(3666) on 2007-05-11 21:24:55 (Show Source):
You can put this solution on YOUR website!.15x+.02(14000-x)=1060
.15x+280-.02x=1060
.15x-.02x=1060-280
.13x=780
x=780/.13
x=6000 answer for the amount invested @ 155.
proof
.15*6000+.02*8000=1060
900+160=1060
1060=1060
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Linear-equations/81688: How do I solve the system by graphing?
3x + y = 6
3x – y = 0
1 solutions
Answer 58540 by checkley75(3666) on 2007-05-11 21:19:48 (Show Source):
You can put this solution on YOUR website!FIRST YOU MUST CONVERT THESE EQUATON TO THE STANDARD LINE FORMULA FORMAT Y=mX+b WHERE THE (m) TERM IS THE SLOPE & THE (b) TERM IS THE Y INTERCEPT.
3X+Y=6, Y=-3X+6
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-Y=-3X, Y=3X
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NOW WE GRAPH:
 (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, of TWO functions y = -3x +6 and y = 3x).
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it would appear from the graph that the solution is (1,3)
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Linear-equations/81696: I'm super lost on this one, can anyone help me solve?
Divide: 24m(4)n(2) – 8m(2)n(3) + 4m(3)n/4m(2)n
1 solutions
Answer 58527 by checkley75(3666) on 2007-05-11 20:53:34 (Show Source):
You can put this solution on YOUR website!24m^4n^2-8m^2n^3+4m^3n/4m^2n because you have a fraction with a denominator of (4m^2n) we need to multiply all other terms by (4m^2n) so we can combine there terms.
[(24m^4n^2)(4m^2n)-(8m^2n^3)(4m^2n)+(4m^3n)]/4m^2n
(96m^6n^3-32m^4n^4+4m^3n)/4m^2n now we cancel wherever possible:
(14m^4n^2-8m^2n^3+m) Noe we extract all common elements thus:
m(14m^3n^2-8mn^3+1) ANSWER.
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Quadratic_Equations/81461: This question is from textbook
y=-x-2x. how do i slove this problem? how do i graph it?
1 solutions
Answer 58461 by checkley75(3666) on 2007-05-10 22:10:41 (Show Source):
You can put this solution on YOUR website!Y=-X-2X YOU COMBINE THE X TERMS THUS:
Y=-3X NOW YOU SET X=0 & SOLVE FOR Y THUS
Y=-3*0
Y=0 THIS GIVES YOU ONE POINT (0,0)
NOW SET X=ANY OTGHER VALUE LIKE 5 AND SOLVE FOR Y THUS
Y=-3*5
Y=-15 THIS GIVES YOU A SECOND SET OF POINTS (5,-15).
NOW PLOT THESE 2 SETS OF POINTS & DRAW A LINE BETWEEN THEM THUS:
 (graph 300x200 pixels, x from -6 to 6, y from -20 to 10, y = -3x).
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Polynomials-and-rational-expressions/81622: This question is from textbook Algebra 1
How do you solve for x when it is in the denominator of a rational expression such as in the following:
1/8 - 3/5 = 1/x What are the restrictions? What is the solution?
1 solutions
Answer 58460 by checkley75(3666) on 2007-05-10 22:03:08 (Show Source):
You can put this solution on YOUR website!THERE ARE NO RESTRICTIONS.
FIRST YOU MUST COMBINE ALL THE FRACTIONS BY FINDING A COMMON DENOMINATOR LIKE 40.
1/8=5*1/40=5/40 & -3/5=-3*8/40=-24/40
5/40-24/40=1/X
(5-24)/40=1/X
-19/40=1/X NOW CROSS MULTIPLY
-19X=40
X=40/-19
X=-40/19 ANSWER.
PROOF
1/8-3/5=1/(-40/19) A FRACTION IN THE DENOMINATOR (-40/19) NEEDS TO BE INVERTED AND THEN MULTIPLIED BY THE NUMERATOR THUS:
1/8-3/5=-19/40
5/40-24/40=-19/40
-19/40=-19/40
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Equations/81469: a sumbmarine is 450 meters below sea level. An airplane is 832 meters above sea level. what is the total distance the plane and the submarine?
1 solutions
Answer 58459 by checkley75(3666) on 2007-05-10 21:55:08 (Show Source):
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Equations/81474: What two integers have a product of 64 and a sum of -20?
1 solutions
Answer 58458 by checkley75(3666) on 2007-05-10 21:53:05 (Show Source):
You can put this solution on YOUR website!X+Y=-20 X=-20-Y &
X*Y=64.
NOW SUBSTITUTE (-20-Y) FOR X IN THE SECOND EQUATION & SOLVE FOR Y
(-20-Y)*Y=64
-20Y-Y^2=64
Y^2+20Y+64=0
(Y+16)(Y+4)=0
Y=16=0
Y=-16 ANSWER. THEN X=-4
Y+4=0
Y=-4 ANSWER. THEN X=-16
PROOF
-16-4=-20
-20=-20 &
-4*-16=64
64=64
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Quadratic_Equations/81539: Find the slope of any line perpendicular to the line through points (3, 12) and (5, 4).
1 solutions
Answer 58457 by checkley75(3666) on 2007-05-10 21:45:46 (Show Source):
You can put this solution on YOUR website!THE SLOPE OF A LINE THROUGH THESE 2 POINTS IS
(Y2-Y1)/(X2-X1)
(4-12)/(5-3)
-8/2
-4 IS THE SLOPE.
THUS FOR ANY LINE TO BE PERPENDICULAR TO THIS LINE IT MUST HAVE A SLOPE OF 1/4 (THE NEGATIVE RECIPRICAL OF 4).
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