Which equation has a constant of proportionality equal to 1? a. y=10/11x b. y= 7/8x c. y= 3/15x d. y=x

An equation is said to have a constant of proportionality if 'x' is a multiple of 'y' or 'y' is a multiple of 'x'.

Now, we have to determine an equation with constant of proportionality as '1'.

1.

This equation has constant of proportionality as ''.

2.

This equation has constant of proportionality as ''.

3.

This equation has constant of proportionality as ''.

4.

This equation has constant of proportionality as '1'.

Option D is the correct  answer.

cross multiplying, we get :

⇒ (3) × (5) = (9) × (x)

⇒ 15 = 9x

d. you cannot tell because there are no values shown.