Which of the following functions results in a graph that shows exponential decay? f(x) = 4(0.8)x f(x) = 0.7(1.2)x f(x) = 12(3)x f(x) = 0.5(2)x

Y=4x^2+x-1 solve using quadratic formula

Jackie purchased 3 bottles of water and 2 cups of coffee for the family for $7.35. ryan 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?

Three numbers x, y, and z are in the ratio 2: 7: 8. if 12 is subtracted from y, then three numbers form a geometric sequence (in the order x, y–12, z). find x, y, and z. there are 2 sets.