7 * х +4 = 22 + 17
7х + 4 = 39
7х = 39-4
7х = 35
х = 35 : 7
х=5
=================
7 * 5 + 4 = 22 + 17
35 + 4 = 39
39=39
50 + 4 * х = 82
4х = 82 - 50
4х = 32
х = 32 :4
х= 8
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50 + 4 * 8 = 82
50 + 32 = 82
82 = 82
3*(х + 6) - 23 = 16
3 * (х + 6) = 16+23
3 * ( х + 6) = 39
х + 6 = 39 : 3
х + 6 = 13
х=13 - 6
х = 7
===============
3*(7+6) - 23 = 16
3 * 13 - 23 = 16
39 - 23 = 16
16 = 16