Answer:
Explanation:
That's an awful lot of points. You don't have to give that many. 10 or 15 points would be more than enough.
The graph touches the x axis at 1 point. That means its basic formula is y = (x - a)^2
Since it upside down, the formula is y = -(x - a)^2. A couple of other things are true.
a = 1 because that's where the graph touches the x axis. y = - x^2 has shifted 1 unit to the right.
Finally the y intercept is -4 which means that the final equation is y = -4(x-1)^2
That's all preliminary. The actual question is, what does the discriminate look like?
y = -4(x^2 - 2x + 1)
y = -4x^2 + 8x - 4
a = - 4
b = 8
c = - 4
sqrt(b^2 - 4ac)
sqrt(8^2 - 4(-4)(-4) )
sqrt(64 - 64) = 0
The answer is the third one. The answer will always be 0 when the graph touches the x axis and does not go through it.