Alternate exterior angles are equal when two parallel lines are cut by a transversal.

Same-side interior angles are supplementary, so the same-side interior angle is 180 - 30 = 150 degrees.

Alternate interior angles are equal, so the alternate interior angle is also 30 degrees.

Alternate exterior angles are equal, so the alternate exterior angle is also 40 degrees, making the other angle 140 degrees.

Same-side interior angles are supplementary, so 180 - 40 = 140 degrees.

Corresponding angles are equal, so the corresponding angle is also 45 degrees.

Corresponding angles are equal, so the angle on the other line is also 70 degrees.

Corresponding angles are equal when two parallel lines are cut by a transversal.

The corresponding interior angle is supplementary to the exterior angle, so it measures 60 degrees.

Alternate interior angles are equal when two parallel lines are cut by a transversal.

When two parallel lines are cut by a transversal, the alternate interior angles are equal.

When a transversal crosses parallel lines, the corresponding angles are equal, and the alternate interior angles are equal, while the consecutive interior angles are supplementary.

Corresponding angles formed by a transversal with parallel lines are equal.

If two lines are parallel, their slopes are equal.

The slopes of perpendicular lines are negative reciprocals. Therefore, the slope is -1/4.

The product of the slopes of two perpendicular lines is -1.

Vertical angles are equal, so the other pair of vertical angles also measures 120 degrees.

Vertical angles are equal, so the other pair of vertical angles also measures 40 degrees.

Vertical angles are equal, so the other pair of vertical angles also measures 45 degrees.

Alternate exterior angles are equal when two parallel lines are cut by a transversal. Thus, the other angle also measures 120 degrees.

Alternate exterior angles are equal when two parallel lines are cut by a transversal. Therefore, the other angle also measures 110 degrees.

By the Alternate Interior Angles Theorem, alternate interior angles are equal. Thus, the other alternate interior angle also measures 120 degrees.

By the Alternate Interior Angles Theorem, alternate interior angles are equal, so the other angle also measures 55 degrees.

Alternate interior angles are equal when two parallel lines are cut by a transversal. Therefore, the alternate interior angle also measures 110 degrees.

Corresponding angles are equal, so the corresponding angle is also 120 degrees.

Same-side interior angles are supplementary. Therefore, the same-side interior angle is 180 - 110 = 70 degrees.

Alternate interior angles are equal when two parallel lines are cut by a transversal. Therefore, the alternate interior angle measures 30 degrees (180 - 150).

Vertically opposite angles are equal. Therefore, the vertically opposite angle is also 30 degrees.

Vertically opposite angles are equal, so the vertically opposite angle is also 30 degrees.

Vertically opposite angles are equal, so the vertically opposite angle is also 30°.