Something funny is that the x value of the vertex lies directl in the middle of the x intercepts so we see the x intercepts or 0's at x=8 and 2 the average is x=5 so find f(5) to find the y value of the vertex f(5)=(5-8)(5-2) f(5)=(-3)(3) f(5)=-9
vertex is at (5,-9)
the actual way the teacher wants is to expand then compltete the square to get into the form f(x)=a(x-h)^2+k where the vertex is (h,k) but whatever
Since the total number of marbles is 40, that is our size of the sample. there are 16 red ones on that sample, so the probability of extracting a red marble from the box is given by the ratio of successes divided the total number of marbles:
