Are the ratios 1/2 and 8/16 a proportion?

Solve by any method (graphing, substitution or linear combination)y = x - 82x + 3y = 1a) (2, -6)b) (5, -3)c) (4, -4)d) (0, -8)i figured it out. the answer is (5, -3)

The table represents a linear function. what is the slope of the function? –6 –4 4 6

How many kilograms of a 5% salt solution and how many kilograms of a 15% salt solution must be mixed together to make 45kg of an 8% salt solution?