Question

pqr is an isosceles triangle in which QR =8cm and PQ =pr 5cm. find the area of the ∆ pqr and length RL which is perpendicular from R on PR ​

Answer 1

Answer:

It is given that, △PQR is isosceles triangle.

∴ PQ=PR=7.5cm

PS⊥QR and RT⊥PQ [ Given ]

⇒ Area of △PQR=

2

1

×QR×PS

=

2

1

×9×6

=9×3

=27cm

2

⇒ Area of △PQR=27cm

2

We can also write,

⇒ Area of △PQR=

2

1

×PQ×RT

⇒ 27=

2

1

×7.5×RT

⇒ 54=7.5×RT

⇒ RT=

7.5

54

⇒ RT=7.2cm