Question

please solve it fast and solve step by step and correctly​

Answer 1

Proof:

AB is perpendicular to DC

• •°• By Pythagoras theorem

AC² = AD² + DC²

AD² = AC² - DC² ........a

And,

AB² = AD² + DB²

AB² = (AC² - DC²) + (DC - BC)² .....from a

AB² = AC² - DC² + DC² - 2BC.DC + BC²

BC² = AC² - DC² + DC² - 2BC.DC + BC² ...AB = BC

BC² = AC² - 2BC.DC + BC²

-AC² = -BC² - 2BC.DC + BC²

-AC² = -2BC.DC

AC² = 2BC.DC ... Proved

Hence, proved that AC² = 2BC.DC .