IDENTIFYING PROPORTIONAL RELATIONSHIPS FROM GRAPHS

Identify the constant of proportionality. Write your answer as y = kx

Problem 1 :

Solution :

Let us get the ratio of y to x.

Constant of proportionality (k) = y/x

k = 9/3

k = 3

y = 3x

k > 1, it is direct proportion.

Problem 2 : 

Solution :

Let us get the ratio of y to x.

Constant of proportionality (k) = y/x

k = 30/6

k = 5

y = 5x

k > 1, it is direct proportion.

Problem 3 :

Solution :

Let us get the ratio of y to x.

Constant of proportionality (k) = y/x

k = 25/5

k = 5

y = 5x

k > 1, it is direct proportion.

Problem 4 :

Solution :

Let us get the ratio of y to x.

Constant of proportionality (k) = y/x

k = 6/1

k = 6

y = 6x

k > 1, it is direct proportion.

Problem 5 :

Solution :

Let us get the ratio of y to x.

Constant of proportionality (k) = y/x

k = 8/2

k = 4

y = 4x

k > 1, it is direct proportion.

Problem 6 :

Solution :

Let us get the ratio of y to x.

Constant of proportionality (k) = y/x

k = 21/7

k = 3

y = 3x

k > 1, it is direct proportion.

Problem 7 :

Solution :

Let us get the ratio of y to x.

Constant of proportionality (k) = y/x

k = 90/10

k = 9

y = 9x

k > 1, it is direct proportion.

Problem 8 :

Solution :

Let us get the ratio of y to x.

Constant of proportionality (k) = y/x

k = 16/8

k = 2

y = 2x

k > 1, it is direct proportion.