Question

help me with this sum

Answer 1

Answer:

Given that X divides PQ in 2:1

= QX = 2/3*PQ. ....(1)

Similarly, Y divides QR in 2:1

= RY = 2/3*QR ......(2)

In ∆PYQ,

PY^2 = PQ^2 + QY^22

PY^2 = PQ^2 + (2/3*QR)^2

9PY^2 = 9PQ^2 + 4QR^2 .......(3)

In ∆XQR,

XR^2 = XQ^2 + QR^2

XR^2 = (2/3*PQ)^2 + QR^2

XR^2 = 4/9*PQ^2 + QR^2

9XR^2 = 4PQ^2 + 9QR^2. ........(4)

On adding (3)+(4), we get

9(PY^2 + XR^2) = 13(PQ^2 + QR^2)

9(PY^2 + XR^2) = 13PR^2

Answer 2

please let me know if you need anything else