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Equations/214021: You are given an endpoint and the midpoint of a line segment. Find the coordinates of the other endpoint. Each midpoint is denoted by M(x, y)
Q (-1,14)
M (2,7)
1 solutions
Answer 161667 by HyperBrain(694)   on 2009-09-15 22:27:11 (Show Source):
You can put this solution on YOUR website!Q (-1,14)
M (2,7)
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Let A(h,k) be the unknown point.
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Using the midpoint formula,
(h+(-1))/2=2
h+(-1)=4
h-1=4
h=5
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Applying the midpoint formula for k,
(k+14)/2=7
k+14=14
k=0
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So, the other endpoint is at (5,0)
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Sequences-and-series/214017: 8 16 14 10 whats the next 3 numbers in the sequence
1 solutions
Answer 161663 by HyperBrain(694) on 2009-09-15 22:14:19 (Show Source):
You can put this solution on YOUR website!8 16 14 10
the first and third terms are 8 and 14. Note that 14=8+6
the second and fourth terms are 16 and 10. Note that 10=16-6
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So, the nth term=(n-2)th term + 6 if n is odd
But, if n is even, nth term =(n-2)th term -6.
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The next term is the 5th term.
Since 5 is odd,
5th term=(5-2)th term + 6=3rd term+6=14+6= 20
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Coordinate-system/190899: This question is from textbook saxon algebra 2
Convert the polar coordinate (5, 2pi/3) to cartesian coordinates.
1 solutions
Answer 160839 by HyperBrain(694) on 2009-09-12 04:32:24 (Show Source):
You can put this solution on YOUR website!Just in case you don't remember:
Given the polar coordinates of a point (r, theta) then it rectangular coordinates is (r cos theta, r sin theta).
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Here:
r=5
theta=2pi/3=120 degrees
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So, the rectangular coordinates of the given point is:
(  ,  )
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Human-and-algebraic-language/212912: In a writing competition, the first place winner receives ½ of the prize money. The second runner up receives ¼ of what the winner won. What was the total amount of prize money distributed if the winner receives $6,000?
1 solutions
Answer 160838 by HyperBrain(694) on 2009-09-12 04:22:50 (Show Source):
You can put this solution on YOUR website!Since the winner receives half of the total prize money,
$6000 is half of the total prize money.
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So, the total prize money is 2($6000)=$12000
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Geometry_proofs/212913: if b is the mid point of ac and c is the mid point of bd, where a,b,c,d lie on a straight line, say why ab=cd?
1 solutions
Answer 160837 by HyperBrain(694) on 2009-09-12 04:21:02 (Show Source):
You can put this solution on YOUR website!Since, b is the midpoint of ac then a, b, and c are collinear (the points lie on the same line)
Since, c is the midpoint of bd then b, c, and d are collinear as well.
So, a, b, c, and d are collinear.
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Since b is the midpoint of ac, then ab=bc
Since c is the midpoint of bd, bc=cd.
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Now, since ab=bc and bc=cd, then
ab=cd
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Trigonometry-basics/207286: If the latitude of Chicago is about 42 degrees and the radius of the earth is about 4000 miles, how far is Chicago from the equator? ( use pi= 3.1416)
1 solutions
Answer 160625 by HyperBrain(694) on 2009-09-11 02:48:39 (Show Source):
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Travel_Word_Problems/212372: Joe drove 210km at 70km/h and then another 210 km at 105km/h. It took Bill the same length of time to drive the entire 420km at constant speed. What was Bill's speed?
1 solutions
Answer 160623 by HyperBrain(694) on 2009-09-11 02:41:33 (Show Source):
You can put this solution on YOUR website!time=distance/speed.
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So, the total time it took for Joe to drive is:
 hr
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speed=distance/time
=-=
So, Bill's speed is:
 km/hr
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Travel_Word_Problems/212373: A motorist driving at 100km/h can go from Wilton to Stockton in 2 hours less time than can a train which averages 75 km/h. How far apart are the two towns?
1 solutions
Answer 160622 by HyperBrain(694) on 2009-09-11 02:38:53 (Show Source):
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Equations/212707: Calculate the density of a block of wood which weighs 750kg and has the dimensions 25cm X 0.10m X 50.0m
1 solutions
Answer 160621 by HyperBrain(694) on 2009-09-11 02:35:03 (Show Source):
You can put this solution on YOUR website!25cm X 0.10m X 50.0m
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So, the volume is 25*0.10*50.0=125 cubic meters
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So, the density is 750 kg/125 cubic meters =6 kg/cubic meter
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Polygons/212711: a regular polygon has an interiaor angle of 170 degrees. how many sides does it have?
is it 3?
1 solutions
Answer 160620 by HyperBrain(694) on 2009-09-11 02:33:20 (Show Source):
You can put this solution on YOUR website!If the interior angle is 170 degrees, the exterior angle is 10 degrees.
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The exterior angle of a regular polygon with n sides has a measure of 360/n degrees.
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So, since the exterior angle of this polygon has measure 10 degrees, then it has 360/10=36 sides.
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Trigonometry-basics/211786: the angle of elevation from the end of the shadow to the top of the building is 63 degrees and the distance is 220 feet.find the length of the shadow to the nearest foot
a)100 feet
b)196 feet
c)432 feet
d)112 feet
1 solutions
Answer 160392 by HyperBrain(694) on 2009-09-09 22:43:14 (Show Source):
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Mixture_Word_Problems/212320: HOW MANY LITERS OF A 10% ALCOHOL SOLUTION MUST BE MIXED WITH 40 L OF A 50% SOLUTION TO GET A 40% SOLUTION?
1 solutions
Answer 160391 by HyperBrain(694) on 2009-09-09 22:40:07 (Show Source):
You can put this solution on YOUR website!Let x=the amount of 10% alcohol solution required
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x L + 40 L = (x+40) L of mixture
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If we have x L of 10% alcohol solution, we have 0.10x L pure alcohol
If we have 40 L of 50% alcohol solution, we have 0.5(40)=20 L pure alcohol
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So, we have the equation:
0.40(x+40)=0.10x+20
40(x+40)=10x+2000
4(x+40)=x+200
4x+160=x+200
3x=40
x= 40/3 L
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Angles/212358: The measure of one angle is 47 degrees less that its supplement. What is the measure of each angle?
1 solutions
Answer 160388 by HyperBrain(694) on 2009-09-09 22:31:45 (Show Source):
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Expressions-with-variables/212325: This question is from textbook
A rectangle and a square have the same width, but the rectangle is 5m longer than the square. Their total area 133m2. Find the dimensions of each figure. Choices for the square's width are 6,7,8.
1 solutions
Answer 160387 by HyperBrain(694) on 2009-09-09 22:30:23 (Show Source):
You can put this solution on YOUR website!Let x=side length of the square=width of the rectangle
Then x+5=length of the rectangle
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The area of the square is x(x)
The area of the rectangle is x(x+5)
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We have the equation:
x(x)+x(x+5)=133
x(x+x+5)=133
x(2x+5)=133
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But, 133=7(19) its only factors
Coincidentally, if x=7, 2x+5=2(7)+5=14+5=19
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So x= 7 m
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Angles/212347: This question is from textbook
the measure of the angle's supplement is 44 less than the measure of the angle. find the measure of the angle's supplement.
1 solutions
Answer 160383 by HyperBrain(694) on 2009-09-09 22:24:44 (Show Source):
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Geometry_Word_Problems/212354: the complement of an angle is one-third the size of the supplement of the same angle. Find the measure of the angle?
1 solutions
Answer 160381 by HyperBrain(694) on 2009-09-09 22:23:25 (Show Source):
You can put this solution on YOUR website!Let x=angle
90-x=complement of the angle
180-x=supplement of the angle
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So, we have the equation:
90-x=1/3(180-x)
multiply both sides by 3, to remove the fraction
3(90-x)=180-x
270-3x=180-x
2x=90
x= 45 degrees
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Trigonometry-basics/212348: This question is from textbook Advanced Mathematics
Find all angles t such that 3t is coterminal with 180 degrees and t is between 0 degrees and 360 degrees.
1 solutions
Answer 160379 by HyperBrain(694) on 2009-09-09 22:20:41 (Show Source):
You can put this solution on YOUR website!I shall use modular arithmetic to solve this one.
An angle x is coterminal with 180 degrees if and only if when if is divided by 360, the remainder is 180.
So,
3t=180 (mod 360)
t=60 (mod 360)
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This is the general modular solution.
Algebraically,
t=360k+60
for all integer values of k
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