CK12 - Geometry

Namethe threepolygonsbelowby their numberof sides.

A. This shapehas sevensides,so it is a heptagon.

B. This shapehas five sides,so it is a pentagon.

C. This shapehas ten sides,so it is a decagon.

Usingthe DistanceFormulaon Polygons

You can use the distanceformulato find the lengthsof sidesof polygonsif they are on a coordinategrid.
Rememberto carefullyassignthe valuesto the variablesto ensureaccuracy. Recallfrom algebrathat you

can find the distancebetweenpoints and usingthe followingformula.

Example 5

A quadrilateralhas beendrawnon the coordinategrid below.

Whatis the lengthof segment?

Use the distanceformulato solvethis problem.The endpointsof are (-3,9)and (4,1).Substitute-3

for , 9 for , 4 for , and 1 for. Thenwe have: