Figure ABCD is a parallelogram.

Parallelogram A B C D is shown. Diagonals are drawn from point A to point C and from point B to point D and intersect at point M. Sides A B and D C are parallel and sides B C and A D are parallel. Angle B M C is (5 x + 25) degrees.

If ABCD is also a rhombus, what must be the value of x?

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