What is the vertex of y=3x^2-30x+77?

(5, 2)

Step-by-step explanation:

Use the formula x = - b/2a to find the x-coordinate of the vertex:

x = - (-30) / [2 (3) ] = 30/6 = 5.

Evaluating the given function at x = 5, we get y = 2.

Thus, the vertex is at (5, 2).