document.write( "Question 141449: y=2x^2+4X-6, find x&y intercepts, coordinates of vertex,graph equation \n" ); document.write( "
Algebra.Com's Answer #103072 by nabla(475)\"\" \"About 
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To find the intercepts, we will first set x=0 and then y=0:\r
\n" ); document.write( "\n" ); document.write( "\"y=-6\" <--- y-intercept
\n" ); document.write( "\"0=2x%5E2%2B4x-6\"
\n" ); document.write( "Now we need to solve the second equation:
\n" ); document.write( "Factor:
\n" ); document.write( "\"0=%282x-2%29%28x%2B3%29\"
\n" ); document.write( "This can only be when x=1 or x=-3. <---x-intercepts\r
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\n" ); document.write( "\n" ); document.write( "The vertex is where the function is at a minimum. I will give you a little calculus after this, but it suffices to say that the vertex is x=-b/(2a) when given a polynomial of form ax^2+bx+c. So the vertex per that formula is: x=-4/4=-1
\n" ); document.write( "which gives a y value of 2-4-6=-8. The ordered pair, then, is (-1,-8).\r
\n" ); document.write( "\n" ); document.write( "Calculus:
\n" ); document.write( "We find the critical points:
\n" ); document.write( "f'(x)=4x+4
\n" ); document.write( "0=4x+4
\n" ); document.write( "-->x=-1
\n" ); document.write( "We then proceed as before, finding that the ordered pair is (-1,-8).\r
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\n" ); document.write( "\n" ); document.write( "Graph:
\n" ); document.write( "\"graph%28+300%2C+200%2C+-5%2C+5%2C+-10%2C+10%2C+2x%5E2%2B4x-6+%29\"
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