Answer:
y = m x + b is the standard form of a straight line
m = (y2 - y1) / (x2 - x1) = (10 - (-8)) / (-3 - 0) = 18 / -3 = -6
When x = 0 y = b from the equation for a line
y = - 8
So our equation is
y = -6 x - 8
As a check let x = -2 then
y = (-6 * -2) - 8 = 12 - 8 = 4
Check on the graph to verify that this equation holds