To solve this, simply multiply each term of your trinomial by each term of your binomial and combine like terms.
2x² + 6x - 8 (x + 3) Multiply each term in the trinomial by x
2x²(x) + 6x(x) - 8(x) = 2x³ + 6x² - 8x
Now, multiply each original term by 3 and add it to your new trinomial.
2x²(3) + 6x(3) - 8(3) = 6x² + 18x - 24
2x³ + 6x² - 8x + (6x² + 18x - 24) Combine the like terms (6x² and 6x², -8x and 18x)
2x³ + 12x² + 10x - 24
There's your answer! I'm not sure I did a great job explaining this, so let me know if I need to elaborate anywhere!
