Answer:
y=-2x+15
Explanation:
First, write out the equation in slope-intercept form, with what you already have:

Let "b" represent the y-intercept.
To find the y-intercept, substitute the point (6,3) in for the "x" and "y" variable of the equation and solve for "b":

Therefore, your y-intercept is 15.
That means your equation is slope-intercept form is y=-2x+15.