Please solve the math question

\[Please\quad tell\quad me\quad the\quad solution\quad of\quad the\quad \\ following\quad question:\\ \\ In\quad \triangle ABC,\quad D\quad is\quad the\quad midpoint\quad of\quad \\ side\quad BC.\quad \angle ACB\quad =\quad { 30 }^{ \circ }.\quad \angle ADB\quad =\quad 45\\ Find\quad \angle BAD.\quad \] I know how to solve it using trigo. But tell me a different method. P.S it's an eighth class question.

#Geometry

Easy Math Editor

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`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
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Comments

DO YOU WANT FULL SOLUTION OR JUST HINT , IF HINT , THEN TRY BY CONSTRUCTION.

ashay wakode - 6 years, 5 months ago

What's your answer, is it 120 ?

Shivam Hinduja - 6 years, 5 months ago

No,it's 30.

ashay wakode - 6 years, 5 months ago

@Ashay Wakode – Your answer is correct

Rajdeep Dhingra - 6 years, 5 months ago

FULL SOLUTION

Rajdeep Dhingra - 6 years, 5 months ago

@ashay wakode Please help

Rajdeep Dhingra - 6 years, 5 months ago

@Sandeep Bhardwaj @Calvin Lin @Steven Zheng @David Mattingly Please help

Rajdeep Dhingra - 6 years, 5 months ago

I believe that this is an NMTC problem. You can view the solution discusssion in this problem. One approach just uses sine rule, while another approach gets more creative.

Calvin Lin Staff - 6 years, 5 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$