Question

In plane P, lines m and n intersect at point A. If line k is perpendicular to line m and line n at point A, then line k is 1) contained in plane p 2) parallel to plane p 3) perpendicular to plane p 4) skew to plane p​

Answer 1

3)

Explanation:

2 lines establish a plane (it is the same plane P as mentioned in the description).

a line being perpendicular (having a right angle = 90°) to 2 other lines means it is perpendicular to the plane these 2 lines are establishing.

as it is impossible for a line to be perpendicular to 2 other lines in the same plane, if these 2 other lines are intersecting. it would only be possible, if these 2 lines were parallel.