The sum of the angles around a point is always 360°.
Given the angles 70°, 100°, and \( x \), we can express this as:
\[ 70° + 100° + x = 360° \]
Now, we can add the known angles:
\[ 170° + x = 360° \]
Next, we can isolate \( x \) by subtracting 170° from both sides:
\[ x = 360° - 170° \] \[ x = 190° \]
Thus, the value of \( x \) is \( \boxed{190°} \).