Answer: y = 4x -11
Remeber the slope is the gradient -> m
Our equation to find the problem:
Substitude:
y-9 = 4(x-5) because y1= 9, x1 = 5 and m = 4
y-9 = 4x - 20 multiply by 4 with the numbers in the bracets
y = 4x -11 - 9 on both sides
therfore our equation that passes through the point (5,9) and has a slope of 4 is y = 4x -11