Answer:
It is proportional. When You graph it, it will go through the origin. The slope is 5. The y intercept is 0.
Explanation:
When a linear function is proportional, the slope will be in the form of y/x.
So, say we put 2 in for x, then y would be 10. 2 is the x and 10 is the y. What is 10/2? 5 (the slope)
If we put in 6 for x, then y would be 30. 5 is the x and 30 would be the y. What is 30/5? 5 (the slope)
if we put in -3 for x, then y would be -15. -3 is the x and -15 would be the y. What is -15/-3? 5 (the slope).
We could not find the slope this way, if the line was not proportional.
For example, if the y intercept is not zero, like
y = 5x + 2. If I put 3 in for the x, then the y would be 17. Is 17/3 equal to 5? No, because the line is not proportional.