Step by step
The question
Question: is y = x proportional?
y = x
Proportional means: y divided by x is always the same number.
We call that number k.
Then y = k times x.
proportional: y ÷ x is always the same
k = y ÷ x, y = kx
1 Look at the equation
It is y = k x, with nothing added.
k = 1.
= y = x → y = kx, k = 1
So it is proportional.
= proportional
2 Check
Let's check on a graph.
We put the points on the grid.
They lie on a straight line through (0, 0).
That is the picture of proportional.
So the answer is right!
Let's look back.
First: look at the equation.
Last: check.
Answer
= proportional