1) х²+2х=t
t²-t-56=0
D=1²-4×(-56)= 1+224=225,( 15)
t1=8 t2=-7
2)х²-8=t
t²+4t-5=0
D=4²-4×(-5)= 16+20=36 (6)
t1=1 t2=-5
1) х²+2х=t
t²-t-56=0
D=1²-4×(-56)= 1+224=225,( 15)
t1=8 t2=-7
2)х²-8=t
t²+4t-5=0
D=4²-4×(-5)= 16+20=36 (6)
t1=1 t2=-5