a
\(71-\left(33+x\right)=26\\ \Rightarrow71-33-x=26\\ \Rightarrow38-x=26\\ \Rightarrow x=38-26\\ \Rightarrow x=12\)
b
\(\left(x+73\right)-26=74\\ \Rightarrow x+73=74+26\\ \Rightarrow x+73=100\\ \Rightarrow x=100-73\\ \Rightarrow x=27\)
c
\(\left(9-x\right)^3=216\\ \Rightarrow\left(9-x\right)^3=6^3\)
\(\Rightarrow\) \(9-x=6\)
\(\Rightarrow x=9-6=3\)
d
\(5.3^{x+1}=135\\ \Rightarrow3^{x+1}=\dfrac{135}{5}=27\\ \Rightarrow3^{x+1}=3^3\\ \Rightarrow x+1=3\\ \Rightarrow x=3-1\\ \Rightarrow x=2\)
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