Question

write an equation for the line, in point slope form, that passes through the points (-5,7) and (-4,-3).

Answer 1

Calculate the slope of line by using formula : m = [(y₂ - y₁)/(x₂ - x₁)], where (x₁, y₁) and (x₂, y₂) are any two points on the line.

The points are (-5, 7) and (-4, -3).

Substitute (x₁, y₁) = (-5, 7) and (x₂, y₂) = (-4, -3) in the slope formula.

m = [(-3) - (7)] / [(-4) - (-5)]

    = (- 3 - 7) / (- 4 + 5)

    = - 10.

The point-slope form of line equation : y - y₁ = m(x - x₁), where m = slope and (x, y) = any point on the line.

We can use either point for (x₁, y₁) in the point-slope form.

Use (-5, 7) ⇒ y - 7 = - 10[x - (-5)].

The point-slope form of line equation is y - 7 = - 10(x + 5) .