Question

Determine whether the formula describes y as a function of x. Explain your reasoning.

y = 9x + 1

Answer 1

Yea but I need a yes or no answer with an explanation please

Answer 2

if you put any vertical line it will cross graph at only one point .
since it pass vertical line test so its function .
graph is

Answer 3

Yes, y is a function of x.
Basically, you're being asked if you can plug some number in for x and get out some other number for y. If this had been x=2y+1, we could say x is a function of y.
Pretty much if the equation is a function with a single variable on one side, we can say that the function is in terms of the lone variable.
@sami-21 is right that we test to see if it's a function at all in the first place with the vertical line test (you can also see this is a function because all lines that are not vertical are functions). But this question isn't just asking if it's a function- it's asking if y is a function of x, and for that, we can say yes.