Упростить
5(х-4)^2 -(9х^2-12х+8)

5(x - 4)² - (9x² - 12x + 8) = 5(x² - 8x + 16) - 9x² + 12x - 8 =

= 5x² - 40x + 80 - 9x² + 12x - 8 = - 4x² - 28x + 72

(A-B)²=A²-2AB+B²

5(x-4)²-(9x²-12x+8)=5(x²-8x+16)-(9x²-12x+8)=

=5x²-40x+80-9x²+12x-8=5x²-9x²-40x+12x+80-8=-4x²-28x+72