Question

Which of the following graph represents expression f(x) = ax² + bx + c(a ≠ 0) when a > 0, b < 0 & c < 0?

• A. Graph A: A coordinate plane with a parabola opening upwards. The vertex of the parabola is above the x-axis, and the parabola intersects the x-axis at two points. The y-intercept is positive.
• B. Graph B: A coordinate plane with a parabola opening upwards. The vertex of the parabola is below the x-axis, and the parabola intersects the x-axis at two points. The y-intercept is negative.
• C. Graph C: A coordinate plane with a parabola opening upwards. The vertex of the parabola is on the x-axis, and the parabola intersects the x-axis at one point. The y-intercept is zero.
• D. Graph D: A coordinate plane with a parabola opening downwards. The vertex of the parabola is below the x-axis, and the parabola intersects the x-axis at two points. The y-intercept is negative.

Answer 1

Answer: (B)

Graph B

Answer 2

For $f(x) = ax^2 + bx + c$ with the conditions:

• $a > 0$: Parabola opens upward.
• $c < 0$: The y-intercept (at $f(0) = c$) is negative.

Graph B shows an upward opening parabola with a vertex below the x-axis and a negative y-intercept. Hence, Graph B is correct.