Is it possible for a line to have a constant rate and not be proportional?

Explanation:

Any linear equation in the form y = mx+b has a constant rate of change, and that rate of change is the slope m. If b = 0, then it turns into y = mx. Here m is the constant of proportionality. Direct proportion equations always go through the origin. If b is nonzero, then y = mx+b will not be proportional.

So for example, y = 2x is proportional while y = 2x+1 is not proportional.

answer: the price of one pound cabbage = $ 0.8

the point (10,8) represents that the cost of 10 pounds cabbage is $ 8

step-by-step explanation:

since, here is a proportional relation between the number of pounds of cabbage (x) and the price in dollars (y).

therefore, we can write,

⇒ y = k x

where k is the constant of proportionality.

now, point (5,4) is in the line.

thus, it will satisfies the above equation of line.

⇒ 4 = 5 k

⇒ k = 0.8

thus, the equation of the line is,

y = 0.8 x

a) for x = 1,

y = 0.8

therefore, the cost of one pound of cabbage is 0.8 dollars.

b) in the below graph (10,8) represents that the cost of 10 pounds of cabbage is 8 dollars.