What ordinate has point C lying on the same straight line with points A (-8; -6), point B (-3; -1)

What ordinate has point C lying on the same straight line with points A (-8; -6), point B (-3; -1) and having an abscissa x = 5.

From the coordinates of two points, you can always construct the canonical equation of the straight line that passes through these points.

xA = -8; xB = -3; yA = -6; yA = -1;

(x – xA) / (xB – xA) = (y – yA) / (yB – yA);

(x – (-8)) / (- 3 – (-8)) = (y – (-6)) / (- 1 – (-6));

(x + 8) / 5 = (y + 6) / 5;

We multiply both sides by 5 and get the equation of the straight line:

x + 8 = y + 6;

Find y at x = 5:

5 + 8 = y + 6;

y = 7.

Answer: y = 7.