Construct a regular pentagon ABCDE in which AB = 3cm.

here's a video of it being done

google can provide many more examples of construction of squares and pentagons and more.

if the pentagon is regular , and _ab is 3cm what is the maesure of _cd

To construct a regular pentagon ABCDE with one side length given, follow these steps:

Step 1: Draw a horizontal line segment AB of length 3 cm.

Step 2: From point B, draw a line perpendicular to AB and mark a point C on this line such that BC = 3 cm. To do this, use a compass and set the width to 3 cm. Place the compass on point B and draw an arc intersecting the perpendicular line. This intersection point will be labeled as C.

Step 3: With point C as the center, draw an arc with a radius of 3 cm. This arc should intersect the line segment AB on the side of point A. Label this point of intersection as D.

Step 4: From point D, draw a line segment perpendicular to AD that intersects the arc drawn in Step 3. This intersection point will be labeled as E.

Step 5: Connect the points A and E to form the pentagon ABCDE.

You have now constructed a regular pentagon ABCDE with one side length AB = 3 cm.