-2x(x + 3) - (x + 1)(x - 2)
//Distribute
= (-2x² - 6x) - (x² - 2x + x - 2)
// Combine like terms
= (-2x² - 6x) - (x² - x - 2)
// Open brackets
= -2x² - 6x - x² + x + 2
//Combine like terms
= - 3x² - 5x + 2
//Factorise
= (1 - 3x)(x + 2)
Answer: (1 - 3x)(x + 2)