What is the largest integer value of m such that the equation 3x^2 - mx + 21 = 0 has no real solutions?

Hint: For b² - 4ac < 0 it has no real solutions,

then a = 3, b = -m and c = 7.

my bad.

so (- m)² - 4 * 3 * 21 < 0    calculate

     m² - 252 < 0                + 252

     m² < 252                    sqrt both sides

     m < 15.87...               round to the nearest integer (16)

m = 16

16 is the answer.

Sorry, I didn't see the "<", I just rounded...