Answer:
x = 4
The diagonals are both 4
Step-by-step explanation:
The fact that the two sides have no letter in common indicates that they are opposite each other or a diagonal. In this case the length is a diagonal. Diagonals in a rectangle are equal.
4x - 12 = x Add 12 to both sides
4x - 12 + 12 = x + 12 Subtract x from each side
4x - x = 12
3x = 12 Divide by 3
3x/3 = 12/3
x = 4
One of the diagonals = 4 because it is x.
