document.write( "Question 687718: Find the equation of the parabola that passes through the points (2,3) and (10,3) and has a max value of y=35.\r
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Algebra.Com's Answer #425335 by ankor@dixie-net.com(22740)\"\" \"About 
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Find the equation of the parabola that passes through the points (2,3) and (10,3) and has a max value of 35
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\n" ); document.write( "From the two points, 2,3 and 10,3, we know the axis of symmetry is halfway between them and is the x coordinate of the max, so we have a third point, 6,35
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\n" ); document.write( "Using the y = ax^2 + bx + c form we can solve for a, b, c; three equations:
\n" ); document.write( "x=2, y=3
\n" ); document.write( "4a + 2b + c = 3
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\n" ); document.write( "x=6, y=35
\n" ); document.write( "36a + 6b + c = 35
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\n" ); document.write( "x=10, y=3
\n" ); document.write( "100a + 10b + c = 35
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\n" ); document.write( "Eliminate c
\n" ); document.write( "36a + 6b + c = 35
\n" ); document.write( "4a + 2b + c = 3
\n" ); document.write( "=------------------subtraction eliminates c
\n" ); document.write( "32a + 4b = 32
\n" ); document.write( "Simplify, divide by 4
\n" ); document.write( "8a + b = 8
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\n" ); document.write( "Eliminate c again
\n" ); document.write( "100a + 10b + c = 3
\n" ); document.write( " 36a + 6b + c = 35
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\n" ); document.write( "64a + 4b = -32
\n" ); document.write( "Simplify, divide by 4
\n" ); document.write( "16a + b = -8
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\n" ); document.write( "Use these two equations to eliminate b
\n" ); document.write( "16a + b = -8
\n" ); document.write( " 8a + b = 8
\n" ); document.write( "---------------subtracting eliminates b, find a
\n" ); document.write( "8a = -16
\n" ); document.write( "a = -16/8
\n" ); document.write( "a = -2
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\n" ); document.write( "Find b using 8a + b = -8
\n" ); document.write( "8(-2) + b = 8
\n" ); document.write( "b = 8 + 16
\n" ); document.write( "b = 24
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\n" ); document.write( "Find c using 4a + 2b + c = 3
\n" ); document.write( "4(-2) + 2(24) + c = 3
\n" ); document.write( "-8 + 48 + c = 3
\n" ); document.write( "c = 3 - 40
\n" ); document.write( "c = -37
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\n" ); document.write( "The equation: y = -2x^2 + 24x -37
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