Question
The graph of the quadratic polynomial y = ax^{2} + bx + c is as shown in the figure. Then :

 b < 0
 a > 0
 c < 0
Hint:
Observe that the parabola is opening downwards which means that the values of y are increasing in the negative direction. What does it tell about the coefficient a of the term ?
Locate the position of the roots of the parabola. Are real roots real or imaginary (no real roots)? What does it tell about the value of the discriminant ?
The correct answer is: c < 0
Clearly, y = represent a parabola opening downwards. Therefore, a < 0
y = cuts negative y axis , Putting x = 0 in the given equation
y = c
y = c
c < 0
Thus, from the above graph c < 0.
Related Questions to study
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