Find x when y=5 in the literal equation 4x+7y=51

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

Which expression will have the same sum as 3_8 + 1/4?

Bobby bought 1.12 pounds of turkey at a cost of 2.50 per pound. carla bought 1.4 pounds of turkey at a cost of 2.20 per pound. who spent more and by much?