How do you find the sum or difference of (5a2 plus 6a plus 2)-(7a2-7a plus 5)?

Answer 1

Combine like terms, adding/subtracting the coefficients:

(5a² + 6a + 2) + (7a² - 7a + 5) = (5+7)a² + (6-7)a + (2+5) = 12a² - a + 7

(5a² + 6a + 2) - (7a² - 7a + 5)

= (5a² + 6a + 2) + (-7a² + 7a - 5) = (5-7)a² + (6+7)a + (2-5) = -2a² + 13a - 3

Answer 2

You combine like terms. So the answer is -2a2 + 13a - 3.