-z² +11z-24=0
coeficienti a = -1, b= 11 , c = 24
Δ= b² - 4ac
Δ= 11² - 4 x (-1) x (-24)
Δ= 121 - 4 x 24
Δ= 121-96
Δ= 25
Solutiile sunt -b +/- √Δ supra 2a = - 11 + √25 supra 2 x (-1)
- 11 + 6 spra -2 = -5 supra -2 = 5 supra 2
10x-14x²+7=0
coeficienti = a = 10, b= -14, c=7
Δ = (-14)² - 4 x 10 x 7
Δ = 196 - 280
Δ= - 88
Δ<0, ecuatia nu are solutie.