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Next time, please include the directions. Here the directions would state, "Solve the following linear equation for x."
15-2x-8-3x=-x-12+4x+43
First: combine like terms: 15 - 8 - 2x - 3x = 3x + 31 => 7 - 5x = 3x + 31, or
8x = 24.
Next, solve the above result for x: x = 24/8 = 3
The solution is x = 3.