Question

How would I find the measure of an interior angle?

Answer 1

Interior angle of what type polygon? Please post diagram and the specific question you have. Thanks. @Banhannah96

Answer 2

Okay, without the specific problem I can't help you much, but here is what I know:

~Alternate Interior Angles Theorem~

What it says - If a transversal intersects two parallel lines, then alternate interior angles are congruent.

What it means - When a transversal, the line that cuts through, intersects with two parallel lines, it creates eight angles, four of which are on the inside, or interior, of the parallel lines. The angles that are diagonal from each other are congruent, or have equal measures.

What it looks like: http://escambia.flvs.net/webdav/educator_geometry_v15/module03/imgs/03_01b_04_03.png

∠4 congruent to ∠6
∠3 congruent to ∠5

You can see the angles that are inside the parallel lines, but on opposite sides of the transversal, are congruent. No matter where the transversal moves, the angles will be congruent.

Answer 3

Supplementary Angles: The sum of the angles is always 180 degrees

~Same Side Interior Angles Theorem~

What it says - If a transversal intersects two parallel lines, then same-side interior angles are supplementary.

What it means - If you think about it, you know that corresponding angles are congruent. Picture the angles being laid on top of each other. Now you know that ∠3 and ∠7 match up, as do ∠2 and ∠6. You know that ∠2 and ∠3 are supplemental because they are adjacent along a line. So just think of it as substituting the different angles to figure out which ones are supplemental and which ones are congruent.

What it looks like: http://escambia.flvs.net/webdav/educator_geometry_v15/module03/imgs/03_01b_04_05.png

Why it's important - When you are trying to find out measures of angles, these types of theorems are very handy.

*Note: This was actually taken straight from my school course. Hope it helps!