When is the graph of f (x) = 2x2 – 5x – 3 negative?​

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  -1/2 < x < 3

Step-by-step explanation:

First you need to find the x-intercepts. Since the leading coefficient is positive, you know the graph is decreasing through the left x-intercept, so will be negative between the x-intercept values.

  f(x) = 2x^2 -5x -3

  f(x) = 2x^2 -6x +x -3

  f(x) = 2x(x -3) +1(x -3)

  f(x) = (2x +1)(x -3)

The x-intercepts are the values of x that make these factors zero:

  2x +1 = 0   ⇒   x = -1/2

  x -3 = 0   ⇒   x = 3

The graph of f(x) is negative on the interval ...

  -1/2 < x < 3

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step-by-step explanation: