1. A quadratic fraction is of the form f(x)= 2x^2+bx+5(adsbygoogle = window.adsbygoogle || []).push({});

Find the values for b where the graph of f(x):

1.just touches the x-axis

2. has two x-intercepts

3.does not cut or touch the x-axis

I've tried using the quadratic formula but i have no idea how to do it when there are two unknowns. For number one i thought it must be when y=0 and i've tried substituting other numbers in but other than that i can't start. Can you please start me off?

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# Quadratic functions

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