Question 122573
FOIL DOESN'T WORK FOR THESE EQUATIONS.
YOU NEED THE QUADRATIC EQUATION TO SOLVE THIS ONE.
{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}}
X^2-2X-4=0
X=(2+-SQRT[-2^2-4*1*-4])/2*1
X=(2+-SQRT[4+16])/2
X=(2+-SQRT20)/2
X=(2+4.472)/2
X=(2+4.472)/2
X=6.472/2
X=3.236 ANSWER.
X=(2-4.472)/2
X=-2.472/2
X=-1.236 ANSWER.