SOLUTION:
Angles which are diagonally opposite in a parallelogram are equivalent to each other.
( 3x + 1 ) and ( x + 27 ) are diagonally opposite.
Therefore:
3x + 1 = x + 27
3x - x = 27 - 1
2x = 26
x = 26 / 2
x = 13
FINAL ANSWER:
Therefore, the answer is:
x = 13
Hope this helps! :)
Have a lovely day! <3