Question 84864
*[invoke completing_the_square 4, 2, -3]


Since we have 


{{{y=4(x+1/4)^2-13/4}}}


Set y=0 and solve for x

{{{0=4(x+1/4)^2-13/4}}}


{{{13/4=4(x+1/4)^2}}} Add {{{13/4}}} to both sides



{{{(13/4)(1/4)=(x+1/4)^2}}} Multiply both sides by {{{1/4}}}


{{{0+-sqrt(13/16)=x+1/4}}} Take the square root of both sides



{{{0+-sqrt(13)/4-1/4=x}}} Subtract {{{1/4}}} from both sides


So our answer is

{{{x=(-1+-sqrt(13))/4}}}

which breaks down to 

{{{x=(-1+sqrt(13))/4}}} or {{{x=(-1-sqrt(13))/4}}}