Answer:
[tex]x = 11[/tex]
Step-by-step explanation:
The missing diagram is shown in the attachment.
A trapezoid is a quadrilateral with just one pair of parallel sides.
The pair of sides that are parallel are the bases.
The pair of angles formed on the same side of the base add up to 180°.
This implies that:
[tex]9x \degree + (7x + 4) \degree = 180 \degree[/tex]
[tex]9x + 7x = 180 - 4[/tex]
[tex]16x = 176[/tex]
[tex]x = \frac{176}{16} [/tex]
[tex] \therefore \: x = 11[/tex]
