Track / Stage 4 / 189 of 340 #449 of 2000

8. If a straight line is perpendicular to two intersecting lines in a plane, then this line is perpendicular to this plane.

This one wants a proof. Work it on paper, read the official solution, then mark yourself honestly — the ladder only means something if the record is true.

I solved it I didn't Skip

Official solution

8. Correct.

Translate the text above into English, please retain the original text's line breaks and format, and output the translation result directly.

Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic, difficulty and ordering added by this site.