Respuesta :

AE || BC

===》 DCB angle = DAE angle

AC /

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Thus :

DCB angle = x

And also we know that the submission of interior angles of any triangle must equals to 180 degrees so :

In BCD triangle :

B + C + D = 180

x + x + D = 180

D = 180 - 2x

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In the other hand we know that :

BDC angle + BDA angle = 180

because they make a straight line together so ;

180 - 2x + 50 = 180

- 2x = 180 - 230

- 2x = - 50

x = 25

And we're done...

Have a great time ♡