PLEASE HELP!! Normal Distributions

The school has received back the end of course exam scores for the ninth grade math exam. The scores are normally distributed with a mean of 78 and a standard deviation of 9. Label the Normal Distribution curve, including the mean and 3 standard deviations on each side of the mean.

(a) x intercepts: -6 and 2

you can obtain these by solving the equation 0=x^2 +4x-12 using your favorite quadratic formula. but it is easy to verify -6 and 2 indeed satisfy this equation.

(b) y intercept: -12

this is obtained by setting x=0: 0^2+4*0-12 = -12

(c) the minimum value is: -16 (this is the vertex)

you can get the vertex by rewriting the equation into the form:

there is no global or local maximum as the function goes to infinity, so only in the limit sense: +infinity.

if it's asking for the proper expression then it could be 8x= .8 each person would get a .1   portion of the turkey