Geometry proofs HELP!!

Match each equation with the operation you can use to solve for the variable. subtract 10. divide by 10. divide by 5. subtract 18. multiply by 10. add 18. add 10. multiply by 5. 5 = 10p arrowright p + 10 = 18 arrowright p + 18 = 5 arrowright 5p = 10 arrowright

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.

Someone this asap for a group of students attends a basketball game. * the group buys x hot dogs at the concession stand for $2 each. * the group buys y drinks at the concession stand for $3 each. the group buys 29 items at the concession stand for a total of $70. how many hot dogs did the group buy?