document.write( "Question 275837: f(x)4x2 + 4x - 3
\n" ); document.write( "I need help to find the intercepts, the vertex and the maximun or minimun.
\n" ); document.write( "I know I need to use the quadratic formula, but I don't know how to apply it to find these three points.
\n" ); document.write( "Thank you for your help.
\n" ); document.write( "Martha
\n" ); document.write( "

Algebra.Com's Answer #201253 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
f(x) = 4x2 + 4x - 3
\n" ); document.write( "I need help to find the intercepts, the vertex and the maximum or minimum.
\n" ); document.write( "y = 4x^2 + 4x - 3
\n" ); document.write( "The y intercept occurs when x=0
\n" ); document.write( "y = 4(0) + 4(0) - 3
\n" ); document.write( "y = -3 is the y intercept
\n" ); document.write( ":
\n" ); document.write( "You can use the quadratic formula to find the x intercepts
\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"
\n" ); document.write( "In this equation a=4, b=4, c=-3
\n" ); document.write( "\"x+=+%28-4+%2B-+sqrt%284%5E2-4%2A4%2A-3+%29%29%2F%282%2A4%29+\"
\n" ); document.write( ":
\n" ); document.write( "\"x+=+%28-4+%2B-+sqrt%2816-%28-48%29+%29%29%2F8+\"
\n" ); document.write( ":
\n" ); document.write( "\"x+=+%28-4+%2B-+sqrt%2816%2B48%29%29%2F8+\"
\n" ); document.write( ":
\n" ); document.write( "\"x+=+%28-4+%2B-+sqrt%2864+%29%29%2F8+\"
\n" ); document.write( "Two solutions
\n" ); document.write( "\"x+=+%28-4+%2B+8%29%2F8+\"
\n" ); document.write( "x = \"4%2F8\"
\n" ); document.write( "x = .5
\n" ); document.write( "and
\n" ); document.write( "\"x+=+%28-4+-+8%29%2F8+\"
\n" ); document.write( "x = \"-12%2F8\"
\n" ); document.write( "x = -1.5
\n" ); document.write( ":
\n" ); document.write( "The x intercepts: x=.5, x=-1.5
\n" ); document.write( ":
\n" ); document.write( "Find the vertex,
\n" ); document.write( "first find the axis of symmetry using the formula x = -b/(2a)
\n" ); document.write( "x = \"%28-4%29%2F%282%2A4%29\"
\n" ); document.write( "x = -.5
\n" ); document.write( "The vertex occurs at x=-.5
\n" ); document.write( ":
\n" ); document.write( "Substitute that in the original equation for find y
\n" ); document.write( "y = 4(-.5^2) + 4(-.5) - 3
\n" ); document.write( "y = 4(.25) -2 - 3
\n" ); document.write( "y = +1 - 2 - 3
\n" ); document.write( "y = -4
\n" ); document.write( ":
\n" ); document.write( "Vertex: x=-.5,y=-4; and it is a minimum
\n" ); document.write( ":
\n" ); document.write( "Looks like this
\n" ); document.write( "\"+graph%28+300%2C+200%2C+-4%2C+4%2C+-6%2C+4%2C+4x%5E2%2B4x-3%29+\"
\n" ); document.write( ":
\n" ); document.write( "The intercepts and vertex should be apparent when you see it on this graph
\n" ); document.write( "
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