∫ two congruent trigonometric rulers ADE and ABC, with angles of 30 and 60 respectively,
∴DE⊥EC,BC⊥EC,DE∥BC
M is the midpoint, and the vertical line MF⊥EC is taken from M.
∴DE∥MF∥BC and EF=FC.
∴△EFM and△△△ CFM are congruent,
Get EM=MC
So △EMC is an isosceles triangle.
2. extend AE to g, so that EG=AE, even DG.
Because AE = eg, DE = EC and angle DEG = AEC, triangle DEG is congruent with AEC.
Because df = AC = DG and angle g = angle DFE,
Because of parallelism, angle BAF= = angle DFE= = angle G = angle EAC, AE divides BAC equally.