Answer:
Recall ...
Angles on a straight Line Total to 180°
So
The angle at the Tip of the triangle = 180-157
=23°.
Now 23 is a part of the triangle...
Recall also..
Total angles in a triangle also Total to 180°.
Now that's a Right angled Triangle...
There's the 90° Angle present
So Total angle =
90° + x° + 23° =180
x=180° – (23+90)
x=67°.