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
\n" );
document.write( "\n" );
document.write( "Can you please help me out? thanks in advance \n" );
document.write( "
Algebra.Com's Answer #425335 by ankor@dixie-net.com(22740)![]() ![]() You can put this solution on YOUR website! Find the equation of the parabola that passes through the points (2,3) and (10,3) and has a max value of 35 \n" ); document.write( ": \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 \n" ); document.write( ": \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 \n" ); document.write( ": \n" ); document.write( "x=6, y=35 \n" ); document.write( "36a + 6b + c = 35 \n" ); document.write( ": \n" ); document.write( "x=10, y=3 \n" ); document.write( "100a + 10b + c = 35 \n" ); document.write( ": \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 \n" ); document.write( ": \n" ); document.write( "Eliminate c again \n" ); document.write( "100a + 10b + c = 3 \n" ); document.write( " 36a + 6b + c = 35 \n" ); document.write( "---------------------- \n" ); document.write( "64a + 4b = -32 \n" ); document.write( "Simplify, divide by 4 \n" ); document.write( "16a + b = -8 \n" ); document.write( ": \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 \n" ); document.write( ": \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 \n" ); document.write( ": \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 \n" ); document.write( ": \n" ); document.write( "The equation: y = -2x^2 + 24x -37 \n" ); document.write( " |