Perkalian silang 3(x+2y)kuadrat-13x(x+2y)+4xkuadrat

3(x+2y)² - 13x(x+2y) + 4x²
= 3(x² + 4xy + 4y²) - 13x² - 26xy +4x²
= 3x² +12xy +12y² - 13x² - 26xy +4x²
= -6x² - 14xy +12y²

= 3(x + 2y)² - 13x(x + 2y) + 4x²
= 3(x² + 4xy + 4y²) - 13x² - 26xy + 4x²
= 3x² - 13x² + 4x² + 12xy - 26xy + 12y²
= -6x² - 14xy + 12y²
Atau
= 12y² - 14xy - 6x²

Semoga berguna +_+