Half a number plus 2.5 times that number equals 18. What is the number?

Don't know how to find x given these segment lengths

Sam is a waiter at a local restaurant where he earns wages of $5 per hour sam figures that he also eams about $3 in tips for each person he serves sam works 6 hours on a particular day. if n represents the number of people sam serves that day, which of the following functions could sam use to figure ehis total earings for the do o a. en) = 30 o b. en) = 5n+ 18

Which statement accurately describes how to perform a 90° clockwise rotation of point a (1,4) around the origin?