Question

type the correct answer in the box. use numerals instead of words. if necessary, use / for the fraction bar.
$overline{ab}$ is parallel to $overline{cd}$, and $overline{ef}$ is perpendicular to $overline{ab}$.
the number of $90^circ$ angles formed by the intersections of $overline{ef}$ and the two parallel lines $overline{ab}$ and $overline{cd}$ is

Explanation:

Step1: Analyze perpendicular intersection

When a line is perpendicular to another line, their intersection forms 4 right ($90^\circ$) angles. So $\overline{EF} \perp \overline{AB}$ creates 4 $90^\circ$ angles.

Step2: Use parallel line property

Since $\overline{AB} \parallel \overline{CD}$, $\overline{EF}$ is also perpendicular to $\overline{CD}$. This intersection also creates 4 $90^\circ$ angles.

Step3: Total right angles calculation

Add the angles from both intersections: $4 + 4 = 8$

Answer:

8