Ответы и объяснения

2012-05-07T19:46:39+04:00
2012-05-07T22:04:40+04:00

 (x+2)^2-49=0

x^2+4x+4-49=0

 x2 + 4x - 45 = 0
D = b2 - 4ac
D = 16 + 180 = 196 = 14^2

x1,2 = -b ± √D/2a
x1 = -4 + 14/2= 10/2= 5
x2 = -4 - 14/2 = - 18/2 = -9
Ответ: x1 = 5; x2 = -9