Answer:
7
Explanation:
no need to panic !
it is actually totally easy.
we have the complete, big angle at U (imagine you turn VU around U into UT) = 178 degrees.
VT is almost a straight line (then that angle would be 180 degrees). but only almost ...
anyway, the other 2 angles are just parts of the big angle, and we see that together they sum up to the big angle, as there is no other space for a part of the big angle left.
so
(14x - 11) + (12x + 7) = 178
14x - 11 + 12x + 7 = 178
26x - 4 = 178
26x = 182
x = 7