Which equation has a solution of r = 13?

Lizette is training for a marathon. at 7: 00 she left her house and ran until 8: 30, then she walked until 11: 30. she covered a total distance of 18 miles. her running speed was six miles per hour faster than her walking speed. find her running and walking speeds in miles per hour.

Type the correct answer in each box. spell all the words correctly, and use numerals instead of words for numbers. if necessary, use / for the fraction bar(s).

Tom travels between the two mile markers shown and then finds his average speed in miles per hour. select the three equations that represent this situation.