∴∠ADB=∠CEB=90 degree
∴∠C+∠CBE=90 degrees, C+∠CAD=90 degrees.
∴∠CBE=∠CAD
∴⊿BDH∽⊿ADC
∵⊿ABD is a right triangle, ∠ ABC = 45 degrees.
∴∠BAC=45
∴BD=AD
∴⊿BDH≌⊿ADC
∴BH=AC
(2)∵BE is the height of the triangle.
∴BE⊥AC
He's back.
∴BH⊥AC