The sum of angles of a concave quadrilateral is

Options

A. more than 360°
B. less than 360°
C. equal to 360°
D. twice of 360°

Answer

To find the sum of angles of a concave quadrilateral, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Definition of a Quadrilateral**: A quadrilateral is a polygon with four sides. It can be either convex or concave. A concave quadrilateral has at least one interior angle greater than 180 degrees.

2. **Use the Formula for the Sum of Angles in a Quadrilateral**: The sum of the interior angles of any quadrilateral can be calculated using the formula:
\[ \text{Sum of angles} = (n - 2) \times 180^\circ \]
where \( n \) is the number of sides. For a quadrilateral, \( n = 4 \).

3. **Substitute the Value of \( n \)**: Plugging \( n = 4 \) into the formula:
\[ \text{Sum of angles} = (4 - 2) \times 180^\circ = 2 \times 180^\circ \]

4. **Calculate the Result**: Now, perform the multiplication:
\[ 2 \times 180^\circ = 360^\circ \]

5. **Conclusion**: Therefore, the sum of the angles of a concave quadrilateral is \( 360^\circ \).

### Final Answer:
The sum of angles of a concave quadrilateral is \( 360^\circ \).