Question

Calculate BC.

Answer 1

In ΔACD, we have

`tan 42^circ = (CD)/(AD)`

`=> 0.9004 = (CD)/20`

CD = 0.9004 × 20 = 18.008 m.

In right ΔABD, we have

`tan 35^circ = (AD)/(BD)`

`=> 0.7002 = 20/(BD)`

`=> BD = 20/0.7002 = 28.56`

∴ BC = BD – CD

= 28.56 – 18.00

= 10.56 m