.
6x + x = 56
7x = 56
x = = 8.
CHECK. 6*8 + 8 = 48 + 8 = 56. ! Correct !
Solved.
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Next time, please do not start with these words "I need to know . . . ".
It is impolite.
You better omit these words, at all.
Or, even better, say "Help me please . . . ", and so on . . . . .
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On solving single linear equation in one unknown see the lesson
- HOW TO solve a linear equation
in this site.