53. Jack and Jill have a total of 80 marbles. Jack has 30 less than twice as many marbles as Jill. How many marbles do they each have?

Aportion of a line bounded by two points is defined as

Create and solve a linear equation that represents the model, where squares and triangles are shown evenly balanced on a balance beam. assume the weight of a square is 1 unit and the weight of a triangle is unknown.

Which of these tables represents a non-linear function?