Question 85166

{{{2+2x-x^2=0}}}  Lets first multiply each term by -1 to get the quadratic in a more recognizable form:

{{{x^2-2x-2=0}}} quadratic in standard form where: 
A=1
B=-2
C=-2

Solve using the quadratic formula
{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}}

{{{x = (2 +- sqrt( (-2)^2-4*1*(-2) ))/(2*1) }}} and this equals:

{{{x = (2 +- sqrt( 4+8))/(2) }}}  which equals:

{{{x = (2 +- sqrt( 12))/(2) }}} and this can be written as:

{{{x = (2 +- sqrt(4*3))/(2) }}} simplifying we get:

{{{x = (2 +- 2sqrt(3))/(2) }}} and this reduces to:

{{{x = (1 +-sqrt(3))}}} 


Hope this helps----ptaylor