Answer:
Step-by-step explanation:
(5x^2 - 3x)(8x^2 + 4x)
gonna use the FOIL method
F (first terms in each set)......5x^2 * 8x^2 = 40x^4
O (outside terms in each set)...5x^2 * 4x = 20x^3
I (inside terms in each set)....-3x * 8x^2 = -24x^3
L (last terms in each set).....-3x * 4x = -12x^2
now we have : 40x^4 + 20x^3 - 24x^3 - 12x^2....combine like terms
40x^4 - 4x^3 - 12x^2 <====
