Find the common difference of the arithmetic
sequence 13,9,5,

-4

Step-by-step explanation:

13 - 9 = 4

9 - 5 = 4

so, we can see that it is decreasing by 4 each time.

common difference is -4

Step-by-step explanation:

The common difference is the amount we add  between terms

13 + d = 9

Subtract 13 from each side

13+d-13 = 9-13

d = -4

Check

9+d = 5

9 + -4 = 5

5= 5

This is true so the common difference is -4

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.