SOLUTION: Let x(1) and x(2) be the real solutions to the equation x^2-sqrt(11)x+2=0 Then the sum x(1)+x(2) is equal to ? I have the answer, but have no idea how to get to it. I

Algebra ->  Radicals -> SOLUTION: Let x(1) and x(2) be the real solutions to the equation x^2-sqrt(11)x+2=0 Then the sum x(1)+x(2) is equal to ? I have the answer, but have no idea how to get to it. I       Log On


   



Question 100479: Let x(1) and x(2) be the real solutions to the equation
x^2-sqrt(11)x+2=0
Then the sum x(1)+x(2) is equal to ?
I have the answer, but have no idea how to get to it.
I think the two solutions are:
1/2(-sqrt(2) + sqrt(11); converted to decimals: 0.951206
and
1/2 (sqrt(2) + sqrt(11); converted to decimals: 2.3654
So x(1)+x(2) = 3.316627
How to work this out? Squaring? (How?), Factoring (How?)

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
x^2-sqrt(11)x+2=0
Use the quadratic formula to get:
x = [sqrt(11) +- sqrt(11-4*2)]/2
x = [sqrt(11) +- sqrt(3)]/2
x1 = [sqrt(11) + sqrt(3)]/2
x2 = [sqrt(11) - sqrt(3)]/2
---------
x1+x2 = sqrt(11)
==============
Cheers,
Stan H.