A group of rangers work 5 days per week. it takes them 4 days to plant trees on 1/2 acre. what is the unit rate per week

Graph y ≥ -x^2 - 1. click on the graph until the correct graph appears.

3x + 4y = 5 x- 3y = -7 solve by substitution

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.