Find to the point slope equation for the line that passes through the points (7,-21) and (-4,23). use the first point in your equation. y + ? = ? (x + ? )

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.