Serena's mom is planning her birthday party. she bought balloons, plates, and cups. serena's mom brought twice as many plates as cups. the number of balloons serena's mom bought was half the number of cups. if serena's mom bought 84 items, how many of each item did she buy.

24 cups, 48 plates, 12 balloons

Step-by-step explanation:

In order to solve for the amount of each item, you can assign one variable and two expressions all of which will have a sum of 84.

c = the number of cups

2c =  the number of plates (twice as many plates as cups)

0.5c = the number of balloons (half of the number of cups)

There was a total of 84 items:

c + 2c + 0.5c = 84

Combine like terms: 3.5c = 84

Divide: 3.5c/3.5 = 84/3.5

Solve for c: c = 24 (cups)

2c = 48 (plates)

0.5c = 12 (balloons)

the anwser is d) 75°

step-by-step explanation:

d. it is a convex pentagon because it has five sides and none of the sides would extend into the inside of the polygon.

step-by-step explanation: