Question

Hi
can anyone tell me how to construct 90° with ruler and compasses.

$please \: answer \: fast.$

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Answer 1

Method 2 of 2: Through the Middle of a Line Segment

• Method 2 of 2: Through the Middle of a Line SegmentDraw a straight line. On a piece of paper, draw a line segment of any convenient length.
• Pick any point on AB. Mark it, and label it O.
• Pick any point on AB. Mark it, and label it O. Grab a compass. Open the compass to a radius a little shorter than either AO or OB.
• Pick any point on AB. Mark it, and label it O. Grab a compass. Open the compass to a radius a little shorter than either AO or OB. Strike two more arcs.
• Pick any point on AB. Mark it, and label it O. Grab a compass. Open the compass to a radius a little shorter than either AO or OB. Strike two more arcs. Draw the 90° angle.