Beginner Vector Geometry #2

There are two vectors, $\overrightarrow{x}=(3,~7)$ and $\overrightarrow{y}=(-8,~9)$ .

Find the value of $\overrightarrow{x}\cdot\overrightarrow{y}$ .

Notation: $\overrightarrow{a}\cdot\overrightarrow{b}$ denotes the inner product of the two vectors $\overrightarrow{a}$ and $\overrightarrow{b}$ .

This problem is a part of <Beginner Vector Geometry> series .