Question

Type the correct answer in the box. Use numerals instead of words. If necessary, use / for the fraction bar.

ABIs parallel to CD, and EFis perpendicular to AB.
The number of 90° angles formed by the intersections of EFand the two parallel lines ABand CDis

Answer 1

8

Explanation:

The four angles formed at each intersection of lines are all 90°.

The total number of 90° angles at the two intersections is 2×4 = 8 90° angles.