Question

5x-2x²-8, 8x³-7x-9, 3+7x² - 2x​

Answer 1

$\huge\underline\mathfrak\red{Answer}$

$5x - 2 {x}^{2} - 8 + (8 {x}^{3} - 7x - 9) + \\ (3 + 7 {x}^{2} - 2x) \\ \\ 5x - 2 {x}^{2} - 8 + 8 {x}^{3} - 7x - 9 + \\ 3 + 7 {x}^{2} - 2x \\ \\ 8 {x}^{3} - 2 {x}^{2} + 7 {x}^{2} + 5x - 7x - 2x \\ - 8 - 9 + 3 \\ \\ 8 {x}^{3} + 5 {x}^{2} - 4x - 14$