The perimeter of this pentagon

The slope of a line is -1/2 . what is the slope of a line that is parallel to it? a. 1/2 b.2 c. -1/2 d. -2

What is the square root of 45? (step by step working plz)

Jackie purchased 3 bottles of water and 2 cups of coffee for a family for $7.35. brian bought 4 bottles of water and 1 cup of coffee for his family for $7.15. how much does each bottle of water cost? how much does each cup of coffee cost? i need this done