Question

find the sum of interior angles of a polygon with sides.

Hint: Start by applying the formula to find the sum of interior angle which is $\left( {2n - 4} \right)90$
Sides= $8$
Sum of interior angles of polygon $= \left( {2n - 4} \right)90$
Here, the value of $n$is $8$, therefore,
$= \left( {16 - 4} \right)90$
$= \left( {12} \right)90$
$= 1080$
Hence, the answer is $1080$.