Final answer:
To simplify the expression (3 - 13x - 7x²) - (5x² + 12x - 10), distribute the negative sign and combine like terms to get -12x² - 25x + 13.
Step-by-step explanation:
To simplify the expression (3 - 13x - 7x²) - (5x² + 12x - 10), we need to distribute the negative sign to each term inside the second parentheses. This gives us 3 - 13x - 7x² - 5x² - 12x + 10. Next, we can combine like terms by adding or subtracting the coefficients of the same degree variables. Combining the x² terms, we have -7x² - 5x² = -12x². Combining the x terms, we have -13x - 12x = -25x. And combining the constant terms, we have 3 + 10 = 13.
So the simplified form of the expression is -12x² - 25x + 13.