Question 820576
An equation is called either f(x) or y.  f(x) = something or y = something.<P>
The slope intercept form of an equation is y = mx + b where b is the y intercept.  It can also appear as f(x) = mx + b.<P>
In your equation, if 7/9 is the value of x, then it's f(x) = 2x + 8 (the general equation), so the y intercept is 8.