Which of the following pairs of functions are inverses of each other?

Si la base de un triángulo isósceles mide 70 m y el ángulo opuesto a ésta mide 58°; entonces ¿cuánto mide la altura de dicho triángulo? a) 21.87 m. b) 40.01 m. c) 43.74 m. d) 63.14 m.

The difference between two numbers is one. three times the larger number minus two times the smaller number is 9. what are the two numbers

The difference of three and the reciprocal of a number is equal to the quotient of 20 and the number. find the number.