Answer:
All the sides of a rhombus are equal and opposite sides parallel and equal.
Therefore by understanding the above we can deduce that:
7x - 4 = 5x + 4
7x - 4 + 4 - 5x = 5x + 4 + 4 - 5x (Separate all the terms with x to go to the other side of the equals sign and do the some for the constants).
7x - 5x + (4 - 4) = (5x - 5x) + 4 + 4
7x - 5x = 4 + 4
2x = 8
2x/2 = 8/2
x = 4
