angles intersecting lines

[Nyla]

SAT math geometry question (Angles - Intersecting lines)

How can I find the angle b in the figure below?

40

Thanks in advance!;);)

[Jack]

SAT math geometry question (Angles - Intersecting lines)


How can I find the angle b in the figure below?

40

Thanks in advance!;);)

Vertical angles are two non adjacent angles formed by a pair of intersecting lines that share a vertex.
Vertical angles are congruent. So, 2a=b (1)

Also, 2a+3a+2a+a=180^o\Rightarrow 8a=180^o\Rightarrow a=22.5^o

Finally from equation (1) we have that b=2a=2\cdot 22.5^o=45^o

Hope these help!!:D:D

[Nyla]

Thank you so much Jack!!