document.write( "Question 395575: find the x-intercepts and y-intercepts\r
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Algebra.Com's Answer #280738 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!


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document.write( "Hi
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document.write( "f(x) = -x^2 +2x+15
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document.write( "Finding x-intercepts when f(x)=0
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document.write( " -x^2 +2x+15 = 0
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document.write( "  |Using Calculator
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document.write( "x = -3, 5  |x-intercepts P(-3,0) and Pt(5,0)
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document.write( "Finding vertex
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document.write( "Using the vertex form of a parabola,  where(h,k) is the vertex
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document.write( "f(x) = -x^2 +2x+15   |completing square to put into vertex form
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document.write( "f(x) = -[(x-1)^2 -1] + 15
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document.write( "f(x) = -(x-1)^2 +1 + 15
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document.write( "f(x) = -(x-1)^2 + 16  Vertex is Pt(1,16)
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