A machine produces 576 units in 18 hours at this rate how many will it produce in 28 hours

Solve: 3x+y=6 4x-2y=18 show all work !

White shapes and black shapes are used in a game. some of the shapes are circles. while the rest are squares. the ratio of the number of white shapes to the number of black shapes is 5: 11. the ratio of the number of white cicrles to the number of white squares is 3: 7. the ratio of the number of black circles to the number of black squres is 3: 8. work out what fraction of all the shapes are circles.

How can writing phrases as algebraic expressions you solve problems?