Does y equals 4x2-9x plus 9 cross the X-axis?

Answer 1

The discriminant will tell you if there are any real roots here, X intercepts or single contact point.

b2 - 4ac

(- 9)2 - 4(4)(9)

81 - 144

= - 63 < 1, so no real roots and the function does not cross the X axis

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