The value of y varies directly with x. which function represents the relationship between x and y when y=2/3 and x=2

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

()1. how do you find range? 2.the following set of data is to be organized into a histogram. if there are to be five intervals on the graph, what should the length of each interval be? 30, 34, 23, 21, 27, 25, 29, 29, 25, 23, 32, 31

Is the square root of 4 plus the square root of 16 rational?