So,
I'm assuming you mean 3x^2 - 5x + 4 = 0.
The discriminant is as follows:
\(b^2 - 4ac\)
Substitute the appropriate numbers.
\(-5^2 - 4(3)(4)\)
Simplify.
\(25 - 4(3)(4)\)
25 - 12(4)
25 - 48
-23
As this is a negative number, there will be two complex roots.
Since complex roots are not real numbers, there will be zero real roots.
