(2х-5у)(4х+3у)-(х+2у)(5х-6у)

Question

(2х-5у)(4х+3у)-(х+2у)(5х-6у)

Answer 1

(2х-5у)(4х+3у)-(х+2у)(5х-6у) = 8x^2 + 6xy - 20xy - 15y^2 - (5x^2 - 6xy + 10xy - 12y^2) = 8x^2 - 14xy - 15y^2 - (5x^2 + 4xy - 12y^2 ) = 
8x^2 - 14xy - 15y^2 - 5x^2 - 4xy+12y^2 = 3x^2 - 3y^2 - 18xy 

Comments

а что это ^

---

спасибо :*

---

степень .

---

аа

Answer 2

(2х-5у)(4х+3у)-(х+2у)(5х-6у) = 8x² + 6xy - 20xy - 15y² - (5x² - 6xy + 10xy - 12y²) = =8x² - 14xy - 15y² - (5x² + 4xy - 12y²) = 
8x² - 14xy - 15y² - 5x² - 4xy+12y² = 3x² - 3y² - 18xy =3*(x² - y² - 6xy)