Уравнение:(x+5)*3/4=9

(х+5)*3/4=9
(х+5)*0,75=9
х+5=9:0,75
х+5=12
х=12-5
х=7
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(х + 5) * 3/4 = 9
х + 5 = 9 : 3/4
х + 5 = 9 * 4/3
х + 5 = 3 * 4
х + 5 = 12
х = 12 - 5
х = 7
(7 + 5) * 3/4 = 9
12 * 3/4 = 9
3 * 3 = 9
9 = 9