Răspunsuri

2014-04-13T18:14:06+03:00
3(1-2x+x²) - 4(x²-4x+4) + 5(x² - 6x + 9) = 4x² - 12x + 9 + 4 - x
3 - 6x + 3x² - 4x² +16x - 16 + 5x² - 30x + 25 = 4x² - 13x + 13
4x² - 20x + 12 = 4x² - 13x + 13
-20x + 12 = -13x + 13
-20x + 13x = 13 - 12
-7x = 1
x = - 1 supra 7