Question

what is the interior angle sum of a heptagon?
900
540
1080
720

Explanation:

Step1: Identify number of sides

A heptagon has $n=7$ sides.

Step2: Use interior angle sum formula

The formula for interior angle sum of a polygon is $(n-2)\times180^\circ$.
Substitute $n=7$:
$$(7-2)\times180^\circ = 5\times180^\circ$$

Step3: Calculate the result

$$5\times180^\circ = 900^\circ$$

Answer:

900