Verify if this is an identity

cot (-x) tanx=-1

7900 dollars is placed in an account with an annual interest rate of 5.5%. How much will be in the account after 11 years, to the nearest cent.

About 40% of all drivers will flash their lights to warn oncoming traffic of a speed trap ahead. suppose seven cars have just driven past a police speed trap. a. what is the probability that at least one of the drivers will warn oncoming traffic? b.

If two variables are inversely related, then as the value of one variable:

4 (3D + 6) - 2D, when D = - 6

At the fair the 'Twirly Tea Cups'ride can hold nine people per tea cup. If the ride has seven tea cups, how many total people can ride at a time?

Lupita rides a taxi that charges a flat rate of $6.75 plus $3.20 per mile. If the taxi charges Lupita $40.03 in total for her trip, how many miles is her ride? Enter your answer in the box as a decimal to the nearest tenth of a mile.

Use the table shows average winter monthly rainfall month November 3/8 month December 1/8 month January 1/2 write river city as percent for each month show your work

Tracey pays $8.50 of her monthly life insurance premium, and her employer covers the rest. If her monthly premium is $32.25, what is the annual value to Tracey of this benefit

Which expression shows 28 + 35 as the product of their greatest common factor and the sum of two whole numbers with no common factor? A. 7 (6 + 3) B. 9 (4 + 3) C. 7 (4 + 5) D. 9 (2 + 5)

You flip a coin three times. a. what is the probability of getting heads on only one of your flips? b. what is the probability of getting heads on at least one flip?