We can use the rule of adjacent angles on a straight line. This means that if the angles which are next to each other are on the same straight line, their sum would be equal to 180°.
So, to solve for x, we can write this equation:
x° = 180° - 47° (abbreviation: adj. ∠s on st. line)
in additional, the answer of x should be 133, note that you don't need to add a degree sign in it because the equation is written as x° instead of x.