Question 1131360
{{{f(x) = -x^2 + 7x + 8}}}

to find the x-intercepts of the graph of f, set {{{f(x) =y=0}}} 

{{{0 = -x^2 + 7x + 8}}}

{{{x^2 -7x -8=0}}}

{{{x^2 +x-8x -8=0}}}

{{{(x^2 +x)-(8x +8)=0}}}

{{{x(x +1)-8(x +1)=0}}}

{{{(x-8)(x +1)=0}}}

=>{{{x=8}}} and {{{x=-1}}}

({{{x}}}, {{{y}}})	 = _({{{-1}}}, {{{0}}})__(smaller x-value)
({{{x}}}, {{{y}}}) = _({{{8}}}, {{{0}}})_(larger x-value)


{{{ graph( 600, 600, -25, 25, -25, 25, -x^2 + 7x + 8) }}}