Hey there!!
We use the distributive property in order to solve this
We will need to distribute one term to the others
2x ( x² + 4x - 3 ) = 2x³ + 8x² - 6x
-3 ( x² + 4x - 3 ) = -3x² - 12x + 9
Get all the terms together and combine the like terms
2x³ + 8x² - 6x - 3x² - 12x + 9
2x³ + 5x² - 18x + 9 is the required answer
Hope my answer helps!