An architect is designing a house on an empty plot. The area of the plot can be modeled by the polynomial 5x^4+12x^2+10x, and the area of the house’s base can be modeled by 3x^3+10x−15. The rest of the plot is the yard. What’s the yard’s area?

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.