Answer:
The value of x is 70°
Explanation:
Lines and Angles
We need to find the value of x that makes lines n and m parallel.
Please refer to the image below where we have added new variables to the original drawing.
If n and m were parallel, then:
y and 30° are corresponding angles, having the same measure.
w and 80° are vertical angles, having the same measure.
If the two above conditions are met, then the triangle has the angles y, w, and x. Since the sum of all internal angles of a triangle is 180°:
x + y + w = 180°
Substituting:
x + 30° + 80° = 180°
Solving for x:
x = 180° - 30° - 80°
x = 70°
The value of x is 70°