Answer:
15+4r
Step-by-step explanation:
15+7r+r(r-3)-r^2
Distribute
15+7r+r^2-3r-r^2
Combine like terms
15+7r-3r+r^2-r^2
15 +4r
15 + 4r
15+7r+r(r-3)-r²
15 + 7r + r² - 3r - r²
