a) \(-x+80=-220-5x\)
\(\Rightarrow-x+5x=-220-80\)
\(\Rightarrow4x=-300\)
\(\Rightarrow x=-\dfrac{300}{4}\)
\(\Rightarrow x=-75\)
b) \(98+\left(x-12\right)+68=-80-x\)
\(\Rightarrow166+\left(x-12\right)=-80-x\)
\(\Rightarrow166+x-12=-80-x\)
\(\Rightarrow154+x=-80-x\)
\(\Rightarrow154+80=-x-x\)
\(\Rightarrow-2x=234\)
\(\Rightarrow x=-\dfrac{234}{2}\)
\(\Rightarrow x=-117\)
c) \(122+x-78=-55-4x-1\)
\(\Rightarrow44+x=-56-4x\)
\(\Rightarrow x+4x=-56-44\)
\(\Rightarrow5x=-100\)
\(\Rightarrow x=-\dfrac{100}{5}\)
\(\Rightarrow x=-20\)
d) \(663+9x=-x-37\)
\(\Rightarrow9x+x=-37-663\)
\(\Rightarrow10x=-700\)
\(\Rightarrow x=-\dfrac{700}{10}\)
\(\Rightarrow x=-70\)