29.Which of the following is an equivalent form of the equation of the graph shown in thexy-plane above, from which the coordinates of vertex V can be identified from constants
in the equation?
A) y = (x − 2)^2 – 16
B) y = x(x − 4) – 12
C) y = (x − 6)(x + 2)
D) y = (x + 6)(x − 2)Here’s How to Crack It
Looking at the graph tells you that the vertex of the parabola is at about (2, –16). Only (A) has the
numbers 2 and 16 in it, so it must be the correct answer. If more than one choice had these constants, you
could use your knowledge of the vertex form. If you recognize that the question is asking for the vertex
form of the equation of the parabola, you can simply select (A), the only choice that actually uses that
form. Finally, if you forget the form, you can multiply out the answers to see which of them match the
original equation. Of course, the test writers have written the answers such that all but (D) are equivalent,