13-7x+2=4
15-7х=4
7х=-11
х=-11/7
7x-2x+3=23
5х=20
х=4
7x-4x-3+5x+3=63
8х=63
х=7,875
12x+3=4x+35
8х=32
13-7x+2=4
15-7х=4
7х=-11
х=-11/7
7x-2x+3=23
5х=20
х=4
7x-4x-3+5x+3=63
8х=63
х=7,875
12x+3=4x+35
8х=32
х=4
13-7x=2
7x=13+2
7x=15
x=15:7
x=15/7
5x=23-3
5x=20
x=4
8x=63
x=63:8
x=7,875
12x+3=4x+35
12x-4x=-3+35
8x=32
x=4