Perform the indicated operation. Be sure the answer is reduced. 3/n2-9 + 7/3-n

What is the area of triangle abc if a = 8, b = 11, and c = 15?

Savannah is painting a striped background for a mural on a wall that is 1515 yards long. she wants a total of 9696 stripes that are all the same width. which calculation should savannah use to decide how wide to make each stripe?

How many different three-digit numbers can be formed using the digits 1 comma 2 comma 9 comma 6 comma 4 comma 3 comma and 8 without repetition? for example, 664 is not allowed.