Question

(a + 2b) (3a +b) - (a + b)(a + 2b) + (a + 2b)^2​

Answer 1

(a + 2b)(3a + b) - (a + b)(a + 2b) + (a + 2b)²

3a² + ab + 6ab + 2b² - {a² + 3ab + 2b²} + a² + 4b² + 4ab

3a² + 4b² + 8ab

3a² + 6ab + 2ab + 4b²

3a(a + 2b) +2b(a + 2b)

(3a + 2b)(a + 2b)