bjr
1) x² - x – 4 = 0
1 x² - 1 x - 4 =0 (a = 1 ; b = -1 ; c = -4)
2) 3x² - 7x + 12 = 0
3x² - 7x + 12 = 0 ( 3 ; -7 ; 12)
3) -4x² -8 x – 3 = 0
-4x² -8 x – 3 = 0 (-4 ; -8 ; -3 )
4) x² + 36 = 0
1 x² + 0 x + 36 = 0 (1 ; 0 ; 36)
5) –x² +2x = 0
-1 x² + 2x + 0 = 0 (-1 ; 2 ; 0)
6) x² - 0.5 x - 9 = 0
1 x² - 0,5 x - 9 = 0 (1 ; -0,5 ; -9)
7) x² + 5.2 x – 4 = 0
1 x² + 5.2 x – 4 = 0 (1 ; 5,2 ; -4)