Given points are .

First find the slope.

Substitute 7 for y₂,  5 for y₁, 4 for x₂, and 2 for x₁  in slope formula.

                 (Product of two same signs is positive)

                 (Add: )

                    (Subtract: )

                        (Divide: )

You know the slope and a point on the line, so use point - slope form with either given point to write an equation of line.

Choose .

  (Substitute 5 for y₁, 2 for x₁ and )

         (Product of two same signs is positive)

    (Apply distributive property: )

            (Multiply: )

Apply addition property of equality: If a = b then a + c = b + c.

(Add 5 to each side)

      (Apply additive inverse property: )

            (Apply additive identity property: )

                  (Add: )

The equation of line is .