The line equation in slope-intercept form is y = mx + b, where m is the slope and b is the y-intercept.

Write the two functions as co-ordinates.

First find the slope

         (Substitute )

             (Product of two same signs is positive)

                (Subtract: – 39 – 9 = – 48)

                   (Add: 11 + 5 = 16)

m = – 3                        (Divide: )

Next find the y-intercept

Substitute the slope and the coordinates of the given point in slope-intercept form equation.

y = mx + b

9 = – 3(– 5) + b                (Substitute – 3 for m, – 5 for x, and 9 for y)

9 = 15 + b                        (Multiply: )

9 – 15 = 15 – 15 + b       (Subtract 15 from each side)

9 – 15 = b                        (Apply additive inverse property: 15 – 15 = 0)

b = – 6                              (Subtract: 9– 15 = – 6)

Finally write the line equation

Substitute the values of slope ‘m’ and y-intercept ‘b’ in slope intercept form line equation.

y = mx + b

y = – 3(x) + (– 6)              (Substitute – 3 for m and – 6 for b)

y = – 3x – 6                      (Simplify)

The function is y = – 3x – 6.