1) We need the table to calculate the slope
2) The point-slope equation is of the form:
(y - y₁) = m (x - x₁), where m is the slope, and x₁ and y₁ are the coordinates of a point in the line.
We have the point (-10,8), so the coordinates are x₁ = -10 and y₁ = 8
3) That leads you to the equation (y - 8) = m (x - ( - 10) )
⇒ y - 8 = m (x + 10).
4) That discards the second and the fourth equations, and let you with these two feasible equations:
y - 8 = - 0.15 (x + 10), and
y - 8 = - 0.2 (x + 10)
5) To find the final equation, you must determine the slope from the table.
That is, take any two set of points and compute slope = (y₂ - y₁) / (x₂ - x₁)
If the result, slope, is - 0.15 then the answer is y - 8 = - 0.15 (x + 10), else, if the result is - 0.2, then the answer is y - 8 = - 0.2 (x + 10)
