How do you rewrite a quadratic formula into vertex form

The graph below shows the height of a projectile t seconds after it is launched. if acceleration due to gravity is -16 ft/s2, which equation models the height of the projectile correctly?

Multiply the polynomials (x+3)(x^2-6x+5)

True or false? the sum of the differences (% - 7) is never zero for any distribution consisting of n observations.