Question

помогите!!!!!!!!!!!!!!!​

Answer 1

1)В
2)Б
3)А
4)Г
5)86^2-14^2
(86-14)(86+14)
72*100=7200
6)(3+х)^2+х^2-9=0
(3+х)^2+(х-3)(х+3)=0
(х+3)(3+х+х-3)=0
(х+3)2х=0
(х+3)х=0
х+3=0
х=0
х=-3