(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Find k such that the graph of y=9x^2 + 3kx + k

A) intersects the x-axis in one point only

B) intersects the x-axis in two points

C) does not intersect the x-axis

2. Relevant equations

D= b^2 − 4ac

y= ax^2+bx+c

quadratic equation

3. The attempt at a solution

I got A but using the discriminent b^2-4ac= 0 meaning there is one root. but I have no idea how to get B and C. The answer is

B) k < 0 or k >4

C) 0<k<4

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# Homework Help: Simple quadratics question

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