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checkley71 answered: 8399 problems
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x-x2-+12=512
1 solutions
Answer 40450 by checkley71(8403)   on 2006-10-30 17:54:37 (Show Source):
You can put this solution on YOUR website!IF YOU HAVE THE RIGHT EQUATION AS FOLLOWS --
X-X^2-12=512 THEN
-X^2-X-514=0 REMOVING THE - SIGNS BY MULTIPLYING ALL TERMS BY -1 WE GET
X^2+X+514=0 NO SIMPLE FACTORING SO WE NEED THE QUADRATIC FORMULA
X=[-B+-SQRT(B^2-4AC)]/2A
X=[-1+-SQRT(1-4*1*514)]/2
X=[-1+-SQRT(1-2056)]/2
X=[-1+-SQRT(-2055)]/2
X=-1/2+45.332i/2
X=-.5+22.666i
AND
X=-1/2-45.332i/2
X=-.5-22.666i
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Complex_Numbers/58970: sketch the parabola  label the intercepts, axis of symmetry, and vertex. i don't understand how to find any of that or how to graph it on a graph if anyone can help please try thank you
1 solutions
Answer 40448 by checkley71(8403) on 2006-10-30 17:43:18 (Show Source):
You can put this solution on YOUR website!ARE YOU SURE YOU COPYED THE EQUATION CORRECTLY?
I GET SOLUTIONS OF
-2+1.1547i &
-2-1.1547i BOTH OF THESE ANSWERS ARE IMMAGINARY NUMBERS -- VERY TOUGH TO GRAPH.
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Vectors/58963: can tou please help me to solve dthis fractions of adding
8 11/15+1 14/15
38 17/20 + 51 9/20 thank you
1 solutions
Answer 40445 by checkley71(8403) on 2006-10-30 17:19:47 (Show Source):
You can put this solution on YOUR website!8 11/15
1 14/15
---------------------
9 25/15 OR
9+1 10/15 OR
10 10/15 OR
10 2/3
38 17/20
51 9/20
----------------
89 26/20 OR
89+1 6/20 OR
90 6/20 OR
90 3/10
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Graphs/58929: 32) the following graph shows the late fee for 2 day care centers. Which one charges the higher late fee? Explain what the slopes represent in this situation.
pg 237#38) The coordinates of the vertices of the triangle ABC are : A(3,8), B(5,4) and C(-3,3). Is ABC a right triangle? Explain.
Idon't know how to show the others. Please help me!
1 solutions
Answer 40444 by checkley71(8403) on 2006-10-30 17:15:01 (Show Source):
You can put this solution on YOUR website!FOR THE PROBLEM OF THE RIGHT ANGLE (?) TRIANGLE.
PLOT THE THREE POINTS AND CHECK WITH A PROTRACTOR FOR A 90 DEGREE ANGLE. YOU WILL FIND NONE. ERGO THIS IS NOT A RIGHT TRIANGLE. I GET ANGLES OF ABOUT 70,80 & 30 DEGREES.
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Complex_Numbers/58958: find an equation of the line through (0,4) and perpindicular to 3x-2y=7
1 solutions
Answer 40443 by checkley71(8403) on 2006-10-30 17:04:27 (Show Source):
You can put this solution on YOUR website!3X-2Y=7
-2Y=-3X+7
Y=3/2X-7/2 THUS THIS LINE HAS A SLOPE OF 3/2
A PERPENDICULAR LINE WOULD HAVE A SLOPE OF -2/3 (A NEGATIVE RECIPRICAL) THUS
Y=mX+b FOR A LINE THROUGH (0,4) HAS A SLOPE OF -2/3 & A Y INTERCEPT OR 4 OR
Y=-2/3X+4
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Triangles/58943: This question is from textbook geometry reasoning
An isosceles triangle has a perimeter of 82 cm. The lengths of th legs of the triangle are represented by (3x + 2) and ( 5x - 14). Find the length of the base of the triangle?
1 solutions
Answer 40442 by checkley71(8403) on 2006-10-30 16:57:24 (Show Source):
You can put this solution on YOUR website!IF (3X+2) & (5X-14) ARE THE EQUAL SIDES THEN
3X+2=5X-14
-2X=-16
X=-16/-2
X=8
THUS THE EQUAL SIDES ARE
3*8+2=24+2=26 OR
5*8-14=40-14=26
SO
82=BASE+26+26
BASE=82-52
B=30 CM.
30+26+26=82
82=82
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real-numbers/58954: I'm confused about negative numbers when you add or subtract them. The problem I am stuck on is five/sixths subtract negative two/thirds? Please help. Kathryn
1 solutions
Answer 40440 by checkley71(8403) on 2006-10-30 16:48:45 (Show Source):
You can put this solution on YOUR website!5/6-(-2/3) A MINUS TIMES A MINUS EQUALS A PLUS SO:
5/6+2/3 NOW FIND A COMMON DENOMINATOR AND ADD
5/6+4/6=9/6=1 3/6 OR 1 1/2 OR 1.5
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Systems-of-equations/58950: hi, i need to re-arrange the formula to solve for x.... -2x+8y=16
heres what i have x=4y-8 but im not sure if this is correct
1 solutions
Answer 40439 by checkley71(8403) on 2006-10-30 16:45:29 (Show Source):
You can put this solution on YOUR website!-2X+8Y=16 TRANFERING THE 8Y TO THE LEFT SIDE OF THE EQUATION CHANGES ITS SIGN
-2X=-8Y+16 NOW DIVIDE ALL TERMS BY (-2) YOU GET
X=-8Y/-2+16/-2 OR
X=4Y-8 YOU GOT IT RIGHT :)
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Linear_Algebra/58946: 6x-y=-4
2x=2y=15
1 solutions
Answer 40437 by checkley71(8403) on 2006-10-30 16:35:20 (Show Source):
You can put this solution on YOUR website!6X-Y=-4
2X+2Y=15 IF THE = BETWEEN THE X & THE 2 SHOULD BE A + & YOU WANT TO SOLVE THIS SET OF EQUATIONS THEN
6X-Y=-4
2X+2Y=15 NOW WE MULTIPLY THE FIRST EQAUTION BY 2 AND ADD THESE 2 EQUATIONS
12X-2Y=-8
-------------------------
14X=7
X=7/14
X=.5 OR 1/2 SUBSTITUTING .5 FOR X IN THE SECOND EQUATION WE GET
2*.5+2Y=15
1+2Y=15
2Y=15-1
2Y=14
Y=14/2
Y=7
PROOF
6*.5-7=-4
3-7=-4
-4=-4
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Exponents/58791: This question is from textbook Mathematics
How do I divide exponents that have negitive bases? I have one problem that has it. It is -16 x to the fourth power divided by -24 x to the 2 power.
1 solutions
Answer 40314 by checkley71(8403) on 2006-10-29 15:35:42 (Show Source):
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Graphs/58780: Write the equation of the line that passes through point (–4, –16) with a slope of 3.
1 solutions
Answer 40312 by checkley71(8403) on 2006-10-29 15:31:59 (Show Source):
You can put this solution on YOUR website!Y=mX+b GIVEN A SLOPE OF 3 WE HAVE
Y=3X+b GIVEN X=-4 & Y=-16 WE HAVE
-16=3(-4)+b
-16=-12+b
b=-16+12
b=-4
THUS THE EQUATION FOR THIS LINE IS
Y=3X-4
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Graphs/58785: Use the following tabe to answer the question.Population of Europe by Age Groups
Population (in thousands)
1950 1970 1995
Age 0-14 143,175 166,367 139,464
Age 15-64 359,162 421,432 487,110
Age 65+ 44,981 68,642 101,338
Age 75+ 14,553 22,762 38,139
Total 547,318 656,441 727,912
Source: European Rural Development (ERD) Project.
What percentage of Europe's population was in the age 75+ group in 1970?
1 solutions
Answer 40308 by checkley71(8403) on 2006-10-29 15:00:06 (Show Source):
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Graphs/58782: Graph 2x – y = 4.
1 solutions
Answer 40305 by checkley71(8403) on 2006-10-29 14:57:06 (Show Source):
You can put this solution on YOUR website!2X-Y=4
-Y=-2X+4
Y=2X-4 SLOPE IS=2 AND THE Y INTERCEPT IS -4
SET Y=O & SOLVE FOR X WE GET
0=2X-4
2X=4
X=2 SO WE NOW HAVE TWO POINTS (2,0) & (0,-4)
PLOT THESE 2 POINTS AND DRAW A LINE THROUGH THEM WITH A SLOPE OF 2
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Miscellaneous_Word_Problems/58755: . Big plane. A six-passenger plane cruises at 180 mph in calm air. If the plane flies 7 miles with the wind I the same amount as it flies 5 miles against the wind, then what is the wind speed?
1 solutions
Answer 40304 by checkley71(8403) on 2006-10-29 14:53:31 (Show Source):
You can put this solution on YOUR website!7/(180+X)=5/(180-X)
5(180+X)=7(180-X)
900+5X=1260-7X
5X+7X=1260-900
12X=360
X=360/12
X=30 MPH IS THE WIND SPEED
PROOF
7/(180+30)=5/(180-30)
7/210=5/150
5*210=7*150
1050=1050
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Functions/58670: This question is from textbook
Solve the sysytems of equations by elimanation
{x=3y=5
{2x=4y=8
and
{5x=3y=8
{2x=4y=8
1 solutions
Answer 40287 by checkley71(8403) on 2006-10-29 13:23:11 (Show Source):
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Linear-equations/58761: I am having problems understanding parabola grafting. Example, if I am given a problem that says:
graph y=-2x (to the second power)
How do I set up my table of solutions for x and y?
1 solutions
Answer 40284 by checkley71(8403) on 2006-10-29 13:11:27 (Show Source):
You can put this solution on YOUR website!Y=-2X^2
SET X=0 THE
Y=2*0^2
Y=O SO WHEN X=0 THEN Y=0
SET X=1 THEN
Y=-2(1)^2
Y=-2*1
Y=-2 SO WHEN X=1 THEN Y=-2
SET X=2 THEN
Y=-2(2)^2
Y=-2(4)
Y=-8 SO WHEN X=2THEN Y=-8
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Travel_Word_Problems/58738: A six-passenger plane cruises at 180 mph in calm air. If the plane flies 7 miles with the wind in the same amount of time as it flies 5 miles against the wind, then what is the speed of the wind?
1 solutions
Answer 40281 by checkley71(8403) on 2006-10-29 12:57:41 (Show Source):
You can put this solution on YOUR website!180/(x+5)=5
180/(x-5)=7
180/(x+5)+2=180/(x-5)
(180+2X+10)/(x+5)=180/(X-5)
(190+2X)/(X+5)=180/(X-5)
180(X+5)=(190+2X)(X-5)
180X+900=190X+2X^2-950-10X
2X^2+190X-10X-180X-950-900=0
2X^2-1850=0
X^2-925=0
(X-30.41)(X+30.41)=0
X-30.41=0
X=30.41 MPH FOR THE WIND.
PROOF
180/(30.42+5)=5
180/35.41=5
5=5
180/(30.41-5)=7
180/25.41=7
7=7
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