What's (3x+1) , (6x-4) in a polygram

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.

Which of the following graphs could represent a quartic function?

Susie wants to take her friend out for lunch. she wants to spend $9.75 each person. how much will she spend in all.