constructions an angle of 90° at a given point on a line
TRANSCRIPT
constructions
An angle of 90° at a given point on a An angle of 90° at a given point on a lineline
constructions
Task: Task: C is a point on line AB.
Centre O, radius OC, draw an arc to cut AB again at D.
Join DO and produce it to meet the circle at E.
Mark any point O outside AB. Join CE.
ECB is 90°.
EC is the perpendicular to AB.
Task: Task: C is a point on line AB. Using ruler and compasses construct an angle
of 90° at C. Construction:Construction:
An angle of 90° at a given point on a An angle of 90° at a given point on a lineline
CA BD
O
EConclusion:Conclusion:
constructions
Conclusion:Conclusion:
ECB is 90°.
EC is the perpendicular to AB.
Task: Task: C is a point on line AB. Using ruler and compasses construct an angle
of 90° at C.
Task:Task:
An angle of 90° at a given point on a An angle of 90° at a given point on a lineline
CA BD
Task: Task: C is a point on line AB.
O
E RESTART
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