As you prepare for the SAT, you’ll definitely want to review quadratic functions. You’ll need to know how to solve quadratic equations, as well as understand the properties of the graphs of these functions.
Here’s a challenging problem involving a quadratic function. Give it a try and then scroll down for the solution.
f(x) = a(x + b)(x – 8)
The equation above represents a quadratic function where a and b are constants. If the function is graphed in the xy-plane, its vertex is at the point (2, -54). What is the value of a + b?
(A) 4
(B) 5.5
(C) 6
(D) 7.5
Continue reading SAT Math: A Challenging Quadratic Function Problem