# Copy a Triangle - Directions

 Do the givens. Draw base of angle by clicking twice in drawing pad. Point A Point B `a=Segment[A,B]` Draw top of angle by clicking once on first point A and then above the base. Point C `b=Segment[A,C]` Label: Use right-click to hide/show labels on endpoints and segment. Draw angle marker by clicking on points B, A and C. `Angle α=Angle[B, A, C]` Decorate: Right-click on angle, choose "Properties", basic tab: Show Label=Name, style tab: size=50. Click on Close. Draw line segment by clicking twice in drawing pad. Point D Point E `c=Line[D,E]` Label: Use right-click to rename D -> P and to hide point E. Copy the angle. Draw circle with radius the base of the angle and center P by clicking on points A, B and P. `Circle d=Circle[P, Segment[A, B]` Draw point D by clicking on 2nd intersection point of circle and line. `C=Intersect[c, b, 2]`. Draw circle with radius the top of the angle and center P by clicking on points A, C and P. `Circle e=Circle[P, Segment[A, C]` Draw circle with radius the segment BC and center P by clicking on points B, C and E. `Circle f=Circle[E, Segment[B, C]` Draw point F by clicking on top intersection point of circles e and f. `F=Intersect[e, f, 1]`. Draw new angle base segment by clicking on points P and E. `g=Segment[P,E]` Draw new angle top segment by clicking on points P and F. `h=Segment[P,F]` Decorate: Right-click on any circle, choose "Properties", style tab: line style=dotted. In left pane of Properties window, select other circles and repeat: line style=dotted. In left pane of Properties window, select line c and change: line style=dashed. Click on Close. Draw angle marker by clicking on points B, A and C. `Angle β=Angle[E, P, F]` Decorate: Right-click on angle β, choose "Properties", basic tab: Show Label=Name, style tab: size=50. Click on Close. Check construction. Click and drag endpoints of ends of angle to change its size. Copied angle should match changes. See construction protocol (Command: View -> Construction Protocol) Save construction. Command: File -> Save.

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Page last modified on January 02, 2010, at 10:45 AM