Factor this expression completely 9a 4 - b 2

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

If x + 10 = 70, what is x? a. 40 b. 50 c. 60 d. 70 e. 80

What is the range of the function? f(x)=-2|x+1|? a. all real numbers. b. all real numbers less than or equal to 0. c. all real numbers less than or equal to 1. d. all real numbers greater than or equal to 1