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##### Asked by: Ursel Quintans

science space and astronomy# How do you construct a copy of an angle with a compass?

**How to Copy an Angle Using a Compass**

**Draw**a working line, l, with point B on it.- Open your
**compass**to any radius r, and**construct**arc (A, r) intersecting the two sides of**angle**A at points Sand T. **Construct**arc (B, r) intersecting line l at somepointV.**Construct**arc (S, ST).**Construct**arc (V, ST) intersecting arc (B, r) atpointW.

Just so, how do you construct an angle with a compass?

**Constructing a 90º Angle**

- Step 1: Draw the arm PA.
- Step 2: Place the point of the compass at P and draw an arcthatcuts the arm at Q.
- Step 3: Place the point of the compass at Q and draw an arcofradius PQ that cuts the arc drawn in Step 2 at R.

**with**a

**line segment**PQ that wewill

**copy**. Mark a point R that will be one endpoint of thenew

**line segment**. Set the

**compasses**' point on thepoint Pof the

**line segment**to be

**copied**. Adjustthe

**compasses**' width to the point Q. The

**compasses**'widthis now equal to the length of the

**linesegment**PQ.

Similarly one may ask, how do you copy a triangle with a compass?

When you **copy a triangle**, the idea is to useyour**compass** to “measure” the lengths of thethreesides of the given **triangle** and then makeanother**triangle** with sides congruent to the sides of theoriginal**triangle**.

An **angle** whose measure is more than 0°butless than 90° is **called** an acute**angle**.**Angles** having magnitudes 30°, 40°,**60**°are all acute **angles**.