Ahhhhhh, I really need help!

What is the reason for the third step in this proof?
Given: a || b, and both lines are cut by transversal t.

Question

Ahhhhhh, I really need help!

What is the reason for the third step in this proof?
Given: a || b, and both lines are cut by transversal t.

anonymous · Answer

attachment

phi · Answer

anonymous · Answer

eh, can you recommend something a little more broken down, like step by step, how to do something like this?

phi · Answer

Just concentrate on the top part:  alternate interior angles theorem

Do you know a pair of " alternate interior angles" when you see them ?

anonymous · Answer

alternating interior angle