Jackson is playing a video game that has 3 castles to conquer within each level. jackson has completed 5 levels so far. if x represents the number of remaining levels to complete, which of the following equations can be used to find the total number of castles jackson will have conquered once he completes the final level?

Anew obstacle course is home to several new types of challenging obstacles. one such obstacle is traversing a 15-stair staircase. to make it more challenging, the stairs are not uniformly spaced. rather, the vertical space between consecutive stairs for the first 10 stairs is 113 feet and the vertical space for the last 5 stairs is 134 feet. what is the total vertical distance traveled ascending and descending the entire 15-stair staircase?