document.write( "Question 389432: Find the x-intercepts of the parabola with vertex (1,1) and y-intercepts (0,-3). \n" ); document.write( "

Algebra.Com's Answer #275992 by lwsshak3(11628) $\"\"$ $\"About$

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The parabola can be defined by the form:
\n" ); document.write( "y=A(x-h)^2+k, h,k representing the (x,y) coordinates of the vertex
\n" ); document.write( "with the given y-intercept coordinates (0,-3) and vertex coordinates(1,1)
\n" ); document.write( "-3=A(0-1)^2+1
\n" ); document.write( "A=-4
\n" ); document.write( "equation of parabola: y=-4(x-1)^2+1
\n" ); document.write( "=-4(X^2-2x+1)+1 =-4x^2+8x-3
\n" ); document.write( "to find x-intercept, set y=0
\n" ); document.write( "0=-4(x-1)^2+1
\n" ); document.write( "4(x-1)^2=1
\n" ); document.write( "(x-1)^2=1/4
\n" ); document.write( "taking sqrt of both sides,
\n" ); document.write( "x-1=ą1/2
\n" ); document.write( "x=1/2 or 3/2\r
\n" ); document.write( "\n" ); document.write( "ans: x -intercepts at 1/2 and 3/2
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