16Hit1600
Advanced MathMediumX-intercepts of a quadratic function

Advanced Math practice question

The function f is defined by f(x) = x² − 6x + 5. At which values of x does the graph of f cross the x-axis?

  1. A. x = 1 and x = 5Correct
  2. B. x = −1 and x = −5
  3. C. x = 2 and x = 3
  4. D. x = 0 and x = 5

Answer: A. x = 1 and x = 5

x² − 6x + 5 = (x − 1)(x − 5).

Why the other answers are wrong

B. x = −1 and x = −5
(x + 1)(x + 5) would give x² + 6x + 5.
C. x = 2 and x = 3
(x − 2)(x − 3) would give x² − 5x + 6.
D. x = 0 and x = 5
f(0) = 5, not 0.

More Advanced Math questions

Not affiliated with the College Board. SAT is a trademark of the College Board.