Slope intercept form looks like this: y=mx+b
Since the slope is known (3), then it can just be substituted in there:
y=3x+b
In order to complete the equation, the y-intercept (b), needs to be found. To do this the given coordinates are substituted into the equation and it’s solved for b.
Coordinates: (x,y) —> (3,5)
The x=3 and the y=5, so those are the values substituted in:
y=3x+b
5=3(3)+ b
5=9+ b
-4 = b
Therefore, the equation of a line that passes through (3,5) and has a slope of 3 is y = 3x - 4
