a) first expand: (2(x+2) - 3(x-1)) x (2(x+2) + 3(x-1))
then distribute: (2x+4-3x+3) x (2x+4+3x-3)
add same terms together and subtract numbers: (-x+7) x (5x-1)
final answer: (-x+7) x (5x+1)
b) same steps as before
I. (5(x-2) - 4(x+3)) x (5(x-2) + 4(x+3))
II. (5x-10-4x-12) x (5x-10+4x+12)
final answer: (x-22) x (9x+2)
