Which expression is a sum?
a) 5(2 + 3)
b) 8 x (6 + 3)
c) 5(2) + 2(6 ÷ 3)
d) (5 + 2) ÷ (2 + 3)

The anwser cause i do not understand just plez

Liz is shipping a package to her friend. the maximum weight of a medium flat-rate box is 20 pounds, including the box which weighs 6 ounces. write and solve an inequality to describe the possible weight in pounds, w, of the contents that liz will ship to her friend if she must use a medium flat-rate box. use the drop-down menus to explain your answer.

What are the solutions for the following system? -2x^2+y=-5 y=-3x^2+5