Given: ∠CAB =90° and AD⊥ BC
and AC = 75 cm, AB = 1 cm and BC = 1.25 cm
Now, In ΔADB and ΔCAB
∠ADB = ∠CAB [each 90°]
∠ABD = ∠CBA [common angle]
∴ ΔADB ~ ΔCAB [by AA similarity]
Since the triangles are similar, hence corresponding sides are in proportional.
⇒ AD = 60 cm