We have that the shape is a pentagon of sorts, and we will have that the sum of the internal angles of a pentagon equals 540°.
Knowing this, we will find the missing interior angle in the shape:
100° + 119° + 88° + 116° + a = 540°
Then, we will have that the missing side we named a, will have a measure of 117°.
Now, by supplementary angles, we will have the following:
117° + x = 180°
When we solve for x, we will have that is has a measure of 63°
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You can determine the total sum of interior angles by the function:
[tex](n-2)\cdot180[/tex]Where n is the number of sides the shape has.