we have
y = 3x² - 12x+10
rewrite the equation in vertex form
y-10=3x²-12x
y-10=3(x²-4x)
y-10+12=3(x²-4x+4)
y+2=3(x-2)²
is a vertical parabola open up
the vertex is a minimum
the vertex is the point (2,-2)
therefore
the minimum value of the function is y=-2
the answer is the option
C. -2
