You have a cup with 19 coins inside. The total inside the cup is $1.30. Determine how many nickels and dimes are inside the cup. Use a system of equations. Be sure to defined the variables and show all your work. PLS HELP!

On a string instrument, the length of a string varies inversely as the frequency of its vibrations. an 11-inch string has a frequency of 400 cylces per second. find the frequency of a 10-icnch string.

1. a parachutist is 800 feet above the ground when she opens her parachute. she then falls at a constant rate of 5 feet per second. select the equation that represents this situation. h = -800t + 5 y = -5x + 800 h = 5t - 800 y = 800x + 5 i need

10% of 1,900,000. show me how you got the answer