Arock is thrown into the air from a bridge and falls to the water below. the height of the ball , h meters, relative to the water t seconds after being thrown is given by h= -5t^2 + 20t + 15a) determine the maximum height of the rock above water b) how long does it take the rock to reach maximum height c) after how many seconds does the rock hit the water

Look at this system of equations. -3x + 3y = 12 y = x + 4 the solution set of this system is best explained by which of these statements? a) the graphs of the equations are the same line because the equations have the same slope and the same y-intercept. the system has infinitely many solutions. b) the graphs of the equations are parallel lines because they have the same slope but different y-intercepts. the system has no solution. c) the graphs of the equations are lines that intersect at one point because the equations have the same slope but different y-intercepts. the system has exactly one solution. d) the graphs of the equations are lines that intersect at one point because the equations have the same slope and the same y-intercept. the system has exactly one solution.