)For the right triangle shown, what is the tangent of angle A?

Express the following as a function of a single angle, cos(60) cos(-20) - sin(60) sin(-20)

The number of revolutions of two pulleys is inversely proportional to their diameters. if a 24-inch diameter pulley making 400 revolutions per minute is belted to an 8-inch diameter pulley, find the number of revolutions per minute of the smaller pulley.

Solve the system of equations. y= 2x y= x^2 - 15