Solve for x in the equation x+10=15

You paint a 1/2 of a wall in 1/4 hour. how long will it take you to paint one wall

[10 points, algebra 2]according to my answer key the restrictions are -1 and 4. but why not positive 1?

Three friends went on a road trip from phoenix, az, to san diego, ca. mark drove 50 percent of the distance. jason drove 1/8 of the distance. andy drove the remainder of the distance. 1. andy thinks he drove 1/4 of the distance from phoenix, az, to san diego, ca. is andy correct? 2. the distance from phoenix, az, to san diego, ca, is 360 miles. how many miles did each person drive? 3. solve the problem. what is the answer in total?