Answer:
x=2
z=80
Explanation:
Since (7x+66) and (11x+78) are a linear pair, their measures are supplementary and therefore add up to 180 degrees. z and (7x+66) are also vertical angles, meaning that they are equal.
7x+66+11x+78=180
18x+144=180
18x=36
x=2
z=7x+66=7(2)+66=14+66=80
Hope this helps!