document.write( "Question 703935: Find the equation of the parabola with vertex (-2,0) and y intercept 4.\r
\n" ); document.write( "\n" ); document.write( "Can you please help me? Thanks so much in advance
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Algebra.Com's Answer #433794 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
First write down the general form
\n" ); document.write( "of a parabola, which is:
\n" ); document.write( "\"+y+=+a%2Ax%5E2+%2B+b%2Ax+%2B+c+\"
\n" ); document.write( "When in this form, the x-coordinate of the vertex
\n" ); document.write( "is at \"+x%5Bv%5D+=+-b%2F%282a%29+\"
\n" ); document.write( "You are given that the vertex is at ( -2,0 ), so I can say
\n" ); document.write( "\"+-2+=+-b%2F%282a%29+\"
\n" ); document.write( "\"+2+=+b%2F%282a%29+\"
\n" ); document.write( "\"+b+=+4a+\"
\n" ); document.write( "---------------
\n" ); document.write( "So far, I have:
\n" ); document.write( "\"+y+=+a%2Ax%5E2+%2B+4a%2Ax+%2B+c+\"
\n" ); document.write( "The y-intercept occurs where \"+x+=+0+\", so
\n" ); document.write( "\"+y+=+a%2A0+%2B+4a%2A0+%2B+c+\"
\n" ); document.write( "\"+y+=+c+\"
\n" ); document.write( "You are given that the y-intercept is \"+y+=+4+\", so
\n" ); document.write( "\"+4+=+c+\"
\n" ); document.write( "----------------
\n" ); document.write( "So far, I have:
\n" ); document.write( "\"+y+=+a%2Ax%5E2+%2B+4a%2Ax+%2B+4+\"
\n" ); document.write( "Now I go back to the vertex at ( -2,0 )
\n" ); document.write( "\"+0+=+a%2A%28-2%29%5E2+%2B+4%2A%28-2%29+%2B+4+\"
\n" ); document.write( "\"+0+=+4a+-+8+%2B+4+\"
\n" ); document.write( "\"+4a+=+8+-+4+\"
\n" ); document.write( "\"+4a+=+4+\"
\n" ); document.write( "\"+a+=+1+\"
\n" ); document.write( "--------------
\n" ); document.write( "Now I have all I need to write the equation
\n" ); document.write( "\"+y+=+1%2Ax%5E2+%2B+4%2A1%2Ax+%2B+4+\"
\n" ); document.write( "\"+y+=+x%5E2+%2B+4x+%2B+4+\" answer
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\n" ); document.write( "check:
\n" ); document.write( "Does it go through ( 0,4) ? ( the y-intercept )
\n" ); document.write( "\"+y+=+x%5E2+%2B+4x+%2B+4+\"
\n" ); document.write( "\"+4+=+0%5E2+%2B+4%2A0+%2B+4+\"
\n" ); document.write( "\"+4+=+4+\"
\n" ); document.write( "OK
\n" ); document.write( "Here's the plot:
\n" ); document.write( "\"+graph%28+400%2C+400%2C+-6%2C+6%2C+-6%2C+10%2C+x%5E2+%2B+4x+%2B+4+%29+\"
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