Question

решить-
(Х+1)*(2+Х)-7=(4*7+2)*х+100

Answer 1

(х + 1) * (2 + х) - 7 = (4 *7 + 2)х + 100
2х + x^2 + 2 + x - 7 = 30x + 100
x^2 + 3x - 30x - 5 - 100 = 0
x^2 - 27x - 105 = 0
D = 729 - 4*(- 105) = 729 + 420 = 1149;  √D = приблизительно 33, 9
х1 = (27 + 33,9) / 2 = 60,9 /2 = 30,45
х2 = (27 - 33,9) / 2 = - 6,9/2 = - 3,45