4)2500-100%
x - 95%
x=2500*95/100=2375
5)x(x^2-7)=6
х³- 7х - 6 = 0
(х+1)(х²-х-6) = 0
х+1=0 или х²-х-6 = 0
х1= -1 Д = 1 + 24 = 25
х2 = (1-5)/2 = -2
х3 = (1+5)/2=3
ответ. х1= -1, х2 = -2, х3 = 3.
4)2500-100%
x - 95%
x=2500*95/100=2375
5)x(x^2-7)=6
х³- 7х - 6 = 0
(х+1)(х²-х-6) = 0
х+1=0 или х²-х-6 = 0
х1= -1 Д = 1 + 24 = 25
х2 = (1-5)/2 = -2
х3 = (1+5)/2=3
ответ. х1= -1, х2 = -2, х3 = 3.