# Question #4d873

Jan 3, 2017

${x}^{\circ} = {109}^{\circ}$

#### Explanation:

The sum of internal angles for a polygon, equals the number $n$ of independent triangles that can be arranged to calculate it's area, times ${180}^{\circ}$. In the present case $n = 3$. (This number equals also the number of sides minus $2$).

So we have ${x}^{\circ} + {121}^{\circ} + {108}^{\circ} + {102}^{\circ} + {100}^{\circ} = 3 \cdot {180}^{\circ}$

Solving for $x$ we get

${x}^{\circ} = {109}^{\circ}$