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That parallelogram in which adjacent sides are perpendicular to each other is called a rectangle. The value of x is 10.
That parallelogram in which adjacent sides are perpendicular to each other is called a rectangle. A rectangle is always a parallelogram and a quadrilateral but the reverse statement may or may not be true.
The angle of a rectangle is always 90°, Also, the sum of the ∠CFD and ∠DFE is ∠CFE which is an angle of the rectangle CDEF. Therefore, we can write,
∠CFD + ∠DFE = 90°
6x + 3x = 90°
9x = 90°
x = 10
Hence, the value of x is 10.
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