Question: Which of the following is the most reasonable way to determine if the graph of the function f(x)=-x^2+4x+5 intersects the x-axis?
A) Factor the equation and set it equal to zero
B) use a graphing calculator and look for the x-intercepts
C) Substitute values of x and check when f(x)=0
D) All of the above
Correct answer: D
Grade: 8 | Topic: Functions | Difficulty: Easy | Standard: 8.F.A.2