help please on these inequalities problems

1-Solve the inequality (s+8)(s-1)$\le$0

2- Solve the inequality x(x+6)>16

3-Solve the inequality 4t^2$\le$9t-2

4-Solve the inequality $\[\frac{3-z}{z+1} \ge 1.\]$

5-For an integer n, the inequality $x^2 + nx + 15 < 0$
has no real solutions in x. Find the number of different possible values of n.

thanks