You can put this solution on YOUR website! Using the distributive property, we can say
(5x-3)*(8x^2-4x+15) = 5x*(8x^2-4x+15)-3*(8x^2-4x+15)
(5x-3)*(8x^2-4x+15) = 5x*(8x^2)+5x*(-4x)+5x*(15)-3*(8x^2)-3*(-4x)-3*(15)
(5x-3)*(8x^2-4x+15) = 40x^3-20x^2+75x-24x^2+12x-45
(5x-3)*(8x^2-4x+15) = 40x^3-44x^2+87x-45