Question

1. ANSWER THE FOLLOWING: (2x1=2)
9. In AABC, if ZA=100°, AD bisects LA and AD is perpendicular
to BC then find 2B.​

Answer 1

Step-by-step explanation:

In triangle ABC , angle A = 100°

In△ABC,∠A=100°

and AD :bisects angle A .andADbisects∠A.

AD perpendicular BC , AD⊥BC

∠A=100°

angle BAD + angle DAC = 100\degree⟹∠BAD+∠DAC=100°

angle BAD + \angle BAD = 100\degree⟹∠BAD+∠BAD=100°

\blue { ( AD \:bisects \: \angle A ) }(ADbisects∠A)

\implies 2\angle BAD = 100\degree⟹2∠BAD=100°

\implies \angle BAD = 50\degree⟹∠BAD=50°

\begin{gathered}In \triangle BAD , \\ \angle B + \angle {BAD} + \angle {BDA } = 180\degree\end{gathered}

In△BAD,

∠B+∠BAD+∠BDA=180°

Please make my answer brainliest

\pink { ( Angle \:sum \: property ) }(Anglesumproperty)

\implies \angle B + 50 + 90 = 180\degree⟹∠B+50+90=180°

\implies \angle B + 140 = 180\degree⟹∠B+140=180°

\implies \angle B = 180\degree - 140 \degree⟹∠B=180°−140°

\implies \angle B = 40\degree⟹∠B=40°

Therefore.,

\red { Value \:of \: \angle B} \green { = 40\degree }Valueof∠B=40°

•••♪