Решите уравнение: (7 - x)(7 + x) + 3х² = 11x + 34

Question

Решите уравнение:
(7 - x)(7 + x) + 3х² = 11x + 34

Answer 1

(7 - x)(7 + x) + 3х² = 11x + 34
49 - x^2 + 3х² = 11x + 34
2x^2 - 11x + 15 = 0
D = 121 - 4*2*15 = 1
x1 = (11 - 1)/4
x1 = 10/4
x1 = 2,5
x2 = (11 + 1)/4
x2 = 3