Question

In a given Triangle, if AD = 7; Angle B = 30, Angle ADC = 90, and angle C = 60, then find BC length

Answer 1

Answer:

28/√3

Step-by-step explanation:

from∆ADC

<C=60°

AD=7cm=p

DC=b

$= > \tan60 = \frac{p}{b } \\ = > \sqrt{3} = \frac{7}{b } \\ = > b = \frac{7}{ \sqrt{3} }$

Again:-

∆ADB

AD=7cm

<B=30°

$\tan30 = \frac{p}{b} \\ = > \frac{1}{ \sqrt{3} } = \frac{7}{b} \\ = > b = 7 \sqrt{3}$

now BC=BD+DC

$= > \frac{7}{ \sqrt{3} } + 7 \sqrt{3} \\ = > \frac{7 + 7 \times 3}{ \sqrt{3} } \\ = > \frac{7 + 21}{ \sqrt{3} } \\ = > \frac{28}{ \sqrt{3} } \\ = > 28 \times 1.732 = 48.496$