Question 29
Graphs of FunctionsWhat is the equation of the quadratic function represented by the graph above?
- A.y = x2 + x − 2
- B.y = x2 − x − 2
- C.y = −x2 − x + 2
- D.y = −x2 + x + 2
Show the answer and explanation
Answer: D (y = −x2 + x + 2)
Explanation
The curve cuts the x-axis at −1 and 2 and opens downwards, so y = −(x + 1)(x − 2) = −x2 + x + 2.