3.
Multiply both sides by abc to get rid of all division parts
−a^2b−a^2c−ab^2+abx−ac^2+acx−b^2c−bc^2+bcx=3abc
"Simplify"
x(ab+ac+bc) = a^2b+a^2c+ab^2+3abc+ac^2+b^2c+bc^2
Factor out x
x(ab+ac+bc) = a^2b+a^2c+ab^2+3abc+ac^2+b^2c+bc^2
Divide both sides by ab+ac+bc
x = (a^2b+a^2c+ab^2+3abc+ac^2+b^2c+bc2)/ab+ac+bc
Hope it helped.
By the way all exponents are alone, meaning they are NOT being multiplied by a variable or being added with other numbers. Sorry if it is confusing.
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