Question

5x - 2x²-8, 8x³-7x-9, 3+ 7x²​

Answer 1

I hope this will help you

Answer 2

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