Question 677714
y = -2{{{(x+1)^2}}}+9
**(will have vertex of (-1,9))**
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y = -2(x+1)(x+1)+9
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y = -2({{{x^2+2x+1)}}}+9
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y = {{{-2x^2-4x-2}}}+9
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y = {{{-2x^2 - 4x + 7}}}
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Using Quadratic Formula for x intercepts
y = {{{-1(2x^2+4x-7)}}}
Divide both sides by -1
0 = {{{2x^2+4x-7}}}
x = {{{(-4+-sqrt((4)^2-4(2)(-7)))/(2(2))}}}
x = {{{(-4+-sqrt(16+56))/4}}}
x = {{{(-4+-sqrt(72))/4}}}
x = {{{(-4+-sqrt(9*4*2))/4}}}
x = {{{(-4+-3*2sqrt(2))/4}}}
x = {{{(-4+-6sqrt(2))/4}}}
x = -1 +/- {{{(3sqrt(2)/2)}}}
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{{{highlight_green(x = -1 + (3sqrt(2)/2)))}}}
{{{highlight_green(x = -1 - (3sqrt(2)/2))}}}
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{{{graph(300,200,-5,5,-5,15,-2x^2-4x+7)}}}
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