What is 300 times 500

Aline has a slope of 1/4 and passes through point (0.4,-1/2). what is the value of the y-intercept?

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

Solve: 3x+y=6 4x-2y=18 show all work !