Is 2x2 + y = 6 Linear?

Figure abcd is a parallelogram. if point c lies on the line x = 2, what is the y-value of point c

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

The u-drive rent-a-truck company plans to spend $13 million on 320 new vehicles. each commercial van will cost $25 comma 000, each small truck $50 comma 000, and each large truck  $80 comma 000. past experience shows that they need twice as many vans as small trucks. how many of each type of vehicle can they buy?