I don't know what you mean by finding the coordinates of this point, but I do know how to find the equation. You have to use point slope form in order to figure this out. The equation for that is as follows:
y - y₁ = m(x - x₁)
Step 1: Find y₁ and x₁ by looking at your point and picking out the x and y values.
x₁ = x
y₁ = y
So... x₁ = -1 and y₁ = 3
Step 2: Find the slope. In this case, the slope is given to us.
slope (m) = 5
Step 3: Plug all information in point slope form and solve.
y - (-1) = 5(x - 3)
y + 1 = 5x - 15
- 1 - 1
------------------------
y = 5x - 16
y = 5x = 16 is your final answer.
