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I tried to find angle $x$ but i couldn't ?. enough assumption are given to solve this problem? Notice::60(right) 70 (left )

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    are the degrees variables? – 2017-02-26
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    Sorry but your image is not clear :-( The angles are not clearly visible. It is better to draw by hand ... – 2017-02-26
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    Is it in Arabic. Top angle is $20$. Lower left is $70$ and Lower right is ? – 2017-02-26
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    @Nirbhay they are 60(right) 70 (left ) – 2017-02-26
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    I think if you search "world hardest geometry problem on YouTube" this will come up. – 2017-02-26

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This is a famous problem if the small vertex is $20^\circ$ and the triangle is isosceles and the interior lines form $50^\circ$ and $60^\circ$ angles with the base. Look up "serenditious angles."

I have seen about four solutions, all of which use pure constructive geometry and all of which are clever. I have never seen a solution that is easy or even only moderately hard to discover.

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I have also seen these called "adventitious" angles.