Answer:
80 units
Step-by-step explanation:
When a figure is dilated by 2, its side measurements are halved. The figure you're seeing shows the quadrilateral after dilation (we can tell by the apostrophes); if U'R' is 40, UR will have to be 80.
UR = 20
Lets put UR as x. We know 2*x = 40, so x = 20.
