Why bracket and open methods such as Bisection, False-point and Newton method, Secant can't find root in positive x-axis?

What is sin 7x/4 ? i need on this urgent trig

Which represents the solution set of the inequality 5x-9 < 21? a. x < 12/5 b. x > 12/5 c. x > 6 d. x < 6

Aprojectile is thrown upward so that its distance above the ground after t seconds is given by the function h(t) = -16t2 + 704t. after how many seconds does the projectile take to reach its maximum height?