Question

in∆PQR, P=30° , Q=90°, R=60° if PR=12cm then find QR​

Answer 1

Answer:

R.E.F.image

In △PQR,∠PQR=90

∘

BY Pythagoras theorem,

PR

2

=PQ

2

+QR

2

⇒(5)

2

=PQ

2

+(4)

2

⇒(5)

2

−(4)

2

=PQ

2

⇒PQ

2

=25−16

⇒PQ

2

=9

⇒PQ=

9

⇒PQ=3

tanR=

QR

PQ

=

4

3

.