The value of x is 20
A parallelogram is a quadrilateral with equal opposite sides
Since the opposite sides of a parallelogram are equal, then the following equation is true
[tex]6x - 57 = 3x + 3[/tex]
Divide through by 3
[tex]2x - 19 = x + 1[/tex]
Collect like terms, in the above equation
[tex]2x - x = 19 +1[/tex]
Evaluate the like terms
[tex]x = 20[/tex]
Hence, the value of x is 20
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