You are being asked to solve for K given F.
Subtract 32 from both sides. Put brackets around the two terms on the left.
(F - 32) = 9/5(K - 273) Multiply both sides by 5/9
5/9(F - 32) = K - 273 Now add 273 to both sides
5/9(F - 32) + 273 = K
You are actually converting the F temperature to Celcius first. Once in degrees C, you are then adding 273 to make it degrees Kelvin.