Solve the equation X-12/4=9
X=44
X=83
X=48
X=25

explanation:

previous steps have made pa≅ pb ≅ st ≅ su. setting the compass width to ab allows you to make tu the same length. then δstu ≅ δpab by the sss congruence postulate, and ∠p ≅ ∠s by the reason cpctc.

it would be 0.18 because when the other choices are converted they equal those two numbers.   hope this !