Question

A pipe cleaner lay across a wire shelf. The wires that make up the shelf are parallel, and the pipe cleaner is a transversal. The parallel wires are labeled a, b, and, c, and the angles are labeled with numbers.

Parallel lines a, b, and c are cut by a pipe cleaner transversal. All angles are described clockwise, from uppercase left. Where line a intersects with the pipe cleaner, the angles are: 1, 2, 4, 3. Where line b intersects with the pipe cleaner, the angles are 5, 6, 8, 7. Where line c intersects with the pipe cleaner, the angles are: 9, 130 degrees, 12, 11.
The measure of one angle is 130°. Which statement is true regarding the 130° angle and angle 3?

They are same-side interior angles, so angle 3 measures 50°.
They are alternate interior angles, so angle 3 also measures 130°.
They are corresponding angles, so angle 3 also measures 130°.
They are alternate exterior angles, so angle 3 measures 50°.

Answer 1

They are alternate interior angles, so angle 3 also measures 130°.

Reason: the 130° angle (upper right at line c) and angle 3 (lower left at line a) lie between lines a and c and are on opposite sides of the transversal, so they are alternate interior and equal.