document.write( "Question 947844: Which kind of function best models the set of data points:
\n" ); document.write( "-1,22 0,6 1,-10 2,-26 and 3,-42?\r
\n" ); document.write( "\n" ); document.write( "linear
\n" ); document.write( "quadratic
\n" ); document.write( "exponential
\n" ); document.write( "non e of the above\r
\n" ); document.write( "\n" ); document.write( "my answer is linear
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Algebra.Com's Answer #578449 by MathLover1(20849)\"\" \"About 
You can put this solution on YOUR website!
first check if they lie in a line:\r
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Solved by pluggable solver: To determine if 3 points lie in a line
The 3 points lie on a same plane. For all points to lie on a line they should satisfy the equation of a line. Hence any two points taken on a line should calculate to the same slope of a line.
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\n" ); document.write( " In order to prove the 3 points to lie on a line, as there exists a unique line containing three points and every line has a unique slope.
\n" ); document.write( " Hence it will be sufficient to prove that the slope calculated taking 2 points at a time should be equal.
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\n" ); document.write( " Slope of line taking points (X1,Y1) and (X2,Y2) is
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\n" ); document.write( " \"slope+=+%28Y2-Y1%29%2F%28X2-X1%29\"
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\n" ); document.write( " \"slope+=+%28%286-22%29%2F%280--1%29%29+=+-16\" ........................(1)
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\n" ); document.write( " Slope of line taking points (X3,Y3) and (X1,Y1) is
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\n" ); document.write( " \"slope+=+%28Y3-Y1%29%2F%28X3-X1%29\"
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\n" ); document.write( " \"slope+=+%28%28-10-22%29%2F%281--1%29%29+=+-16\" ........................(2)
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\n" ); document.write( " From conditions (1) and (2)
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\n" ); document.write( " The slopes are equal hence the 3 points can lie on same line.
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\n" ); document.write( " If the slope calculated from points (X2,Y2) and (X3,Y3) comes out to be same then it is confirmed that the 3 points lie on a same line.
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\n" ); document.write( " \"slope+=+%28Y3-Y2%29%2F%28X3-X2%29\"
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\n" ); document.write( " \"slope+=+%28%28-10-6%29%2F%281-0%29%29+=+-16\" ........................(3)
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\n" ); document.write( " From (1),(2) and (3)
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\n" ); document.write( " Hence, It is proved that the 3 points lie on same line.
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\n" ); document.write( " To read more on equations of a line refer to articles on wikipedia
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Solved by pluggable solver: To determine if 3 points lie in a line
The 3 points lie on a same plane. For all points to lie on a line they should satisfy the equation of a line. Hence any two points taken on a line should calculate to the same slope of a line.
\n" ); document.write( "
\n" ); document.write( " In order to prove the 3 points to lie on a line, as there exists a unique line containing three points and every line has a unique slope.
\n" ); document.write( " Hence it will be sufficient to prove that the slope calculated taking 2 points at a time should be equal.
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " Slope of line taking points (X1,Y1) and (X2,Y2) is
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\n" ); document.write( " \"slope+=+%28Y2-Y1%29%2F%28X2-X1%29\"
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\n" ); document.write( " \"slope+=+%28%28-26--42%29%2F%282-3%29%29+=+-16\" ........................(1)
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\n" ); document.write( " Slope of line taking points (X3,Y3) and (X1,Y1) is
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\n" ); document.write( " \"slope+=+%28Y3-Y1%29%2F%28X3-X1%29\"
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\n" ); document.write( " \"slope+=+%28%28-10--42%29%2F%281-3%29%29+=+-16\" ........................(2)
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\n" ); document.write( " From conditions (1) and (2)
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\n" ); document.write( " The slopes are equal hence the 3 points can lie on same line.
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " If the slope calculated from points (X2,Y2) and (X3,Y3) comes out to be same then it is confirmed that the 3 points lie on a same line.
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\n" ); document.write( " \"slope+=+%28Y3-Y2%29%2F%28X3-X2%29\"
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\n" ); document.write( " \"slope+=+%28%28-10--26%29%2F%281-2%29%29+=+-16\" ........................(3)
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\n" ); document.write( " From (1),(2) and (3)
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\n" ); document.write( " Hence, It is proved that the 3 points lie on same line.
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\n" ); document.write( " To read more on equations of a line refer to articles on wikipedia
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\n" ); document.write( "\n" ); document.write( "since all points lie in a line, choose two of them and find linear equation:\r
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Solved by pluggable solver: Find the equation of line going through points
hahaWe are trying to find equation of form y=ax+b, where a is slope, and b is intercept, which passes through points (x1, y1) = (1, -10) and (x2, y2) = (0, 6).
\n" ); document.write( " Slope a is \"a+=+%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29+=+%286--10%29%2F%280-1%29+=+-16\".
\n" ); document.write( " Intercept is found from equation \"a%2Ax%5B1%5D%2Bb+=+y%5B1%5D\", or \"-16%2A1+%2Bb+=+6\". From that,
\n" ); document.write( " intercept b is \"b=y%5B1%5D-a%2Ax%5B1%5D\", or \"b=-10--16%2A1+=+6\".
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\n" ); document.write( " y=(-16)x + (6)
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\n" ); document.write( " Your graph:
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\n" ); document.write( "\n" ); document.write( "so, answer is: linear
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