Can you plz me i don't understand this

Marcus needs to rewrite f(x) = x2 + 6x + 4 in vertex form.

Aball is thrown from a height of 139 feet with an initial downward velocity of 15 ft/s. the ball's height h (in feet) after t seconds is given by the following. h=139-15t-16t^2 how long after the ball is thrown does it hit the ground? round your answer(s) to the nearest hundredth. (if there is more than one answer, use the "or" button.) t =

Which inequality has a dashed boundary line when graphed ?