keeping in mind that 29/6 is greater than 4, is actually 4 and 5/6, so the amount we'll "add" will be a negative one.
[tex]\bf \cfrac{29}{6}+x=4\implies x=4-\cfrac{29}{6}\implies x=\cfrac{4}{1}-\cfrac{29}{6}\implies x=\cfrac{(6)4-(1)29}{6}
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x=\cfrac{24-29}{6}\implies x=\cfrac{-5}{6}\\\\
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\cfrac{29}{6}+\left( -\cfrac{5}{6} \right)=4[/tex]
