document.write( "Question 32365This question is from textbook Elementary and Intermediate alegbra
\n" );
document.write( ": I need to find the equation of the parabola that has an ordered pair (1,1), (0,2), and (3,5) as points on the graph. I need to leave the answer in the form y= ax2 + bx +c.\r
\n" );
document.write( "\n" );
document.write( "Thanks\r
\n" );
document.write( "\n" );
document.write( "Sherri \n" );
document.write( "
Algebra.Com's Answer #18924 by mukhopadhyay(490)![]() ![]() ![]() You can put this solution on YOUR website! The standard equation of a parabola is y = ax^2+bx+c \n" ); document.write( "Substitute the ordered pairs in the above equation. \n" ); document.write( "For (1,1): 1 = a+b+c.........(1) \n" ); document.write( "For (0,2): 4 = c.............(2) \n" ); document.write( "For (3,5): 5 = 9a+3b+c......(3) \n" ); document.write( "From(2), we know c=4 \n" ); document.write( "From (1) and (3): \n" ); document.write( "a+b = -3......(4) \n" ); document.write( "9a+3b=1......(5) \n" ); document.write( "Multiply (4) with -3: \n" ); document.write( "-3a-3b = 9 \n" ); document.write( "9a+3b = 1 \n" ); document.write( "Sum above two equations: \n" ); document.write( "6a = 10 \n" ); document.write( "=>a=5/3 \n" ); document.write( "Using equation (4): b=-3 - 5/3=-14/3 \n" ); document.write( "The required equation is y = (5/3)x^2-(14/3)x+4 \n" ); document.write( " |