The slope m of a non vertical line through any two points is given by,

(Substitute  )

       (Product two same signs is positive) \ \

       (Add: )

             (Add: )

            (Divide: )

Slope .

The line equation in point-slope form is  ,

where m is the slope and  where is a given point on a nonvertical line.

Substitute , x₁ = 4 and y₁ = 4 in point-slope form equation.

 (Product two same signs is positive)

Apply multiplication property equality:Multiply each side by 4.

(Cancel common terms) \ \

Distribute terms using distributive property: a(b + c) = ab + bc.

      (Multiply: )

Apply subtraction property equality:Subtract 16 from each side.

 (Apply additive inverse proeprty: )

       (Apply additive identity property: )

            (Subtract: )

Apply division property equality:Divide each side by 4.

            (Cancel common terms)

The line equation is .