document.write( "Question 231995: Find the x-intercepts of the parabola with vertex (6,-5) and y-intercept (o,175). Write your answer in this form: (x1,y1),(x2,y2). If necessary, round to the nearest hundredth. \n" ); document.write( "
Algebra.Com's Answer #171549 by josmiceli(19441)\"\" \"About 
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If the equation is in the form
\n" ); document.write( "\"y+=+ax%5E2+%2B+bx+%2B+c\" , then the x component
\n" ); document.write( "of the vertex is at
\n" ); document.write( "and, plugging the point into general equation,
\n" ); document.write( "\"y+=+ax%5E2+%2B+bx+%2B+c\"
\n" ); document.write( "\"-5+=+a%2A6%5E2+%2B+b%2A6+%2B+c\"
\n" ); document.write( "(2) \"-5+=+36a+%2B+6b+%2B+c\"
\n" ); document.write( "---------------------------
\n" ); document.write( "The y-intercept is at (0,175), so plugging this into
\n" ); document.write( "general equation:
\n" ); document.write( "\"175+=+a%2A0%5E2+%2B+b%2A0+%2B+c\"
\n" ); document.write( "(3) \"175+=+c\"
\n" ); document.write( "Now I have 3 equations and 3 unknowns, so it's solvable
\n" ); document.write( "From (1),
\n" ); document.write( "(1) \"6+=+-%28b%2F2a%29\"
\n" ); document.write( "\"b+=+-12a\"
\n" ); document.write( "Plug this into (2)
\n" ); document.write( "(2) \"-5+=+36a+%2B+6b+%2B+c\"
\n" ); document.write( "(2) \"-5+=+36a+%2B+6%2A%28-12a%29+%2B+c\"
\n" ); document.write( "also, from(3),
\n" ); document.write( "(2) \"-5+=+36a+%2B+6%2A%28-12a%29+%2B+175\"
\n" ); document.write( "\"36a+-+72a+=+-175+-5\"
\n" ); document.write( "\"-36a+=+-180\"
\n" ); document.write( "\"a+=+5\"
\n" ); document.write( "and, since
\n" ); document.write( "\"b+=+-12a\"
\n" ); document.write( "\"b+=+-12%2A5\"
\n" ); document.write( "\"b+=+-60\"
\n" ); document.write( "Now I can write the actual equation
\n" ); document.write( "\"y+=+5x%5E2+-+60x+%2B+175\"
\n" ); document.write( "Set \"y+=+0\" to find x-intercepts
\n" ); document.write( "Then divide through by \"5\"
\n" ); document.write( "\"x%5E2+-+12x+%2B+35+=+0\"
\n" ); document.write( "I can see right away that it factors into
\n" ); document.write( "\"%28x+-+5%29%28x+-+7%29+=+0\"
\n" ); document.write( "\"x+=+5\" and \"x+=+7\" are the solutions
\n" ); document.write( "So, the x-intercepts are at (5,0) and (7,0)\r
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