Ingat sifat perpangkatan : $\frac{1}{a^m}=a^{-m}$

Maka,

$7^{-2}-\left(-\frac{97}{49}\right)=7^{-2}+\frac{97}{49}$

$=\frac{1}{7^2}+\frac{97}{49}$

$=\frac{1}{49}+\frac{97}{49}$

$=\frac{98}{49}$

$=2$