Question 48581
2x^2 + x - 1 = 0 
I'll do one and let you do the rest:
1st: Identify a,b,c for the problem:
In this case a=2,b=1,c=-1
2nd: Evaluate b^2-4ac
In this case you get 1^2-4(2)(-1) =1+8=9
3rd: If the value is > there are two real unequal roots
If the value is 0 there are two real equal roots
If the value is <0 there are two uneqal complex roots
In this case, since the value is 9, there are two real unequal roots.

I'll leave the rest to you.
Cheers,
Stan H.