13. R(x) = *-16 x+ 2 Pr 1 14. Use: s(t) = -16t2 + Vot + So to model the parabolic motion of a ball tossed straight up into the air with an initial velocity of 15 ft/sec, from an initial height of 3 ft. What is the maximum height the ball will reach? Pro 15. Determine the x-values that cause the polynomial function to be (a) zero, (b) positive, and (c) negative. f (x) = (x+2)(x+1)(x-1) 16. Solve the inequality. 17. Solve the inequalities2 - 2x - 1 2 0 (x + 10)(x+8)(x -6)>0