#z_1 / z_2 = (r_1 / r_2) (cos (theta_1 - theta_2) + i sin (theta_1 - theta_2))#
#z_1 = 8 + i, z_2 = -2 - 9 i#
#r_1 = sqrt(8^2 + 1^2)^2) = sqrt 65#
#theta_1 = tan ^ (1)/ (8) = 7.125^@ = , " I Quadrant"#
#r_2 = sqrt(-2^2 + (-9)^2) = sqrt 85#
#theta_2 = tan ^-1 (-9/ -2) ~~ 257.4712^@, " III Quadrant"#
#z_1 / z_2 = sqrt(65 / 85) (cos (7.125 - 257.4712) + i sin (7.125 - 257.4712))#
#color(blue)(=> -0.2941 + 0.8235 i)#