Question

5x + 9 + x + 2x = 81 - x

Answer 1

5x + 9 + x + 2x = 81 - x
=> 5x + x + 2x + x = 81 - 9
=> 9x = 72
=> x = 72/9
=> x = 8

hope it helps u...

Answer 2

$5x + 9 + x + 2x = 81 - x \\ 8 x + 9 + x = 81 \\ 9x + 9 = 81 \\ 9( x + 1) = 81 \\ x + 1 = \frac{81}{9} \\ x + 1 = 9 \\ x = 8$
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