Hello there!
Part A: Solve for n; -n*p - 90 < 30
Add 90 to both sides.
-n*p < 120
Divide both sides by p.
-n < 120/p
Divide both sides by -1.
n [tex] \geq [/tex] 120/-p is your answer for part A.
Part B: Solve for h; 5m - 3h = 45
Subtract 5m from both sides.
-3h = -5m + 45
Divide both sides by -3.
h = (-5m + 45)/-3 is your answer for part B.
I hope this helps!