The equation of line and circle Given the vertex a (3, - 1) of △ ABC, the linear equation of the middle line on the edge AB is 6x + 10y-59 = 0, The equation of bisector line of ∠ B is: x-4y = 10 = 0, the equation of straight line of BC is obtained

The equation of line and circle Given the vertex a (3, - 1) of △ ABC, the linear equation of the middle line on the edge AB is 6x + 10y-59 = 0, The equation of bisector line of ∠ B is: x-4y = 10 = 0, the equation of straight line of BC is obtained

Let the coordinates of B be (a, b), then the midpoint coordinates of AB are m {(3 + a) / 2, (B-1) / 2}, because point B is on the straight line x-4y + 10 = 0, so a-4b + 10 = 0 ① And because the midpoint m is on the straight line 6x + 10y-59 = 0, the equation 3A + 5B = 55 is brought in ② Simultaneous equations