For what value of x is line a parallel to line b?
x=?
URGENT THANKSSSS
Answer:
[tex]x=30[/tex]
Step-by-step explanation:
According to Corresponding Angles Theorem, given one pair of parallel lines cut by another transversal one, the pair of corresponding angles have the same measure.
Therefore:
[tex]2x+20=80\\2x=60\Rightarrow x=30[/tex]
Geometrically proving:
Since the angle [tex](2x+20)[/tex] is 80º then we can state its Alternate Interior angle (in blue) values also 80º. In addition to this, the Vertex Angle Theorem confirms that.
Algebraically, just plug in 30º for x, then solve it to prove it:
[tex]2(30)+20=80\Rightarrow 80=80[/tex]