Question

In triangle PQR, PS is a median and QS =3.5 cm, then find QR?

Answer 1

Step-by-step explanation:

Use Apollonius theorem

$pq {}^{2} + qr {}^{2} = 2(ps {}^{2} + qs {}^{2} )$

Plug in the given values to get QR

Answer 2

QR = 7 cm.

Step-by-step explanation:

The joining line between one vertex and the midpoint of the opposite side of a triangle is called a median of the triangle.

Now, if PS is a median of triangle Δ ABC, then the point S will be the midpoint of QR and hence QS = SR

⇒ QR = (QS + SR) = 2 × QS

Now, QS is given to be 3.5 cm.

Hence, QR = 3.5 × 2 = 7 cm. (Answer)