In ΔCAD and ΔCBD,
CD = CD [ Common side ]
AD = BD [ CD is the perpendicular "bisector" of AB ]
∠CDA = ∠CDB [ CD is the "perpendicular" bisector of AB ]
Thus, ΔCAD and ΔCBD are congruent triangles. [ SAS congruency ]
If these triangles are congruent, then AC = BC.
2x = 3x -10
x = 10.
