Respuesta :

Answer:

-7r^2+12r-8

Step-by-step explanation:

Answer:

- 7r² + 12r - 8

Step-by-step explanation:

Given

(10 + 7r - r² ) + (- 6r² - 18 + 5r) ← remove parenthesis

= 10 + 7r - r² - 6r² - 18 + 5r ← collect like terms

= - 7r² + 12r - 8