First find the slope of the two coordinates.
Slope is represented by the equation:
M = y2 - y1 / x2 - x1
Substitute in the coordinates.
M = 9 - 8 / -15 - (-10)
M = 9 - 8 / -15 + 10
M = 1 / -5
M = - 1/5
Then use the equation a line:
y - y1 = m(x - x1)
y - 8 = -1/5(x - (-10)
y - 8 = -1/5(x + 10)
y - 8 = -1/5x - 2
y = -1/5x + 6 is the solution
