Răspunsuri

2014-08-29T19:43:42+03:00
x+7 =  \sqrt{(5-x)(3x+11)}
Ridici ecuatia la puterea a doua si o sa obtii:
(x+7)^{2} = (5-x)(3x+11)
x^{2}+14x+49 = 15x+55-3x^{2}-11x
x^{2}+14x+49 = 4x+55-3x^{2}
4x^{2}+10x-6 = 0
Δ = 100+96 = 196
 x_{1} = (-10+√196)/8 = (-10+14)/8 = 4/8 = 1/2
 x_{2} = (-10-√196)/8 =  (-10-14)/8 = (-24)/8 = -3