Which is the equation of the line?

a.
4x – y = –2

b.
x – 4y = –8

c.
4x + y = 2

d.
x + 4y = –8

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.