z1:z2 = (2+3i)/(4-6i) = (2+3i)(4+6i)/(4-6i)(4+6i) = (8+12i+12i+18i^2)/(16-36i^2) =
=(8+24i-18)/(16+36) = (24i-10)/52
z1:z2 = (2+3i)/(4-6i) = (2+3i)(4+6i)/(4-6i)(4+6i) = (8+12i+12i+18i^2)/(16-36i^2) =
=(8+24i-18)/(16+36) = (24i-10)/52