Find the values of the function y = x2 - 4x - 21 for the given values of x, x = - 2, 0, 2.

Answer 1

not quite calculus, but al you have to do is substitute in the values of x.

for x=0 -> y=x^2-4x-21 is y=0^2-4*0-21 = 0-0-21 = -21

you're just looking at specific points along the parabola and seeing what the y value is.