Question

In traingle PQR, PD is perpendicular to QR such that D lies on QR . if PQ = a, PR =b , QD=c and DR= d, prove that (a+b) (a-b) = (c+d) (c-d)​

Answer 1

Step-by-step explanation:

Given In A PQR, PD 1 QR, PQ = a, PR = b,QD = c and DR =d

To prove (a + b) (a-b) = (c + d)(c-d)

Proof In right angled ΔPDQ,

PQ² = PD²+ QD² [ By Pathagoras theorem]

a² = PD² + c²

PD² = a²– c²