Question

select the correct answer.
a regular convex polygon has an exterior angle measure of (20^circ). how many sides does the polygon have?
a. 20
b. 18
c. 22
d. 16

Explanation:

Step1: Recall exterior angle sum rule

The sum of exterior angles of any convex polygon is $360^\circ$. For a regular polygon, all exterior angles are equal.

Step2: Calculate number of sides

Let $n$ = number of sides. Use formula $n = \frac{360^\circ}{\text{measure of one exterior angle}}$.
Substitute the given exterior angle:
$n = \frac{360}{20}$

Step3: Compute the value

$n = 18$

Answer:

B. 18