angles of a polygon

The sum of the interior angles of the polygon shown is 900°.
Solution:
Number of sides of the polygon (n) = 7
Sum of interior angles of a polygon formula:
[tex]\text {Sum}=(n-2) \times 180^{\circ}[/tex]
Substitute n = 7 in the formula.
[tex]=(7-2) \times 180^{\circ}[/tex]
[tex]=5 \times 180^{\circ}[/tex]
[tex]=900^{\circ}[/tex]
The sum of the interior angles of the polygon shown is 900°.