Example: Subtraction of Areas from a Calculation

In the following example, the closed polyline represents a metal plate with two large holes. You first calculate the area of the polyline and then subtract each hole. AutoCAD LT displays area and perimeter or circumference of each object and a running total after each step.

Command: Enter area

<First point>/Object/Add/Subtract: Enter a

<First point>/Object/Subtract: Enter o

(ADD mode) Select objects: Select the polyline

Area = 0.34, Perimeter = 2.71

Total area = 0.34

(ADD mode) Select objects: Press ENTER

<First point>/Object/Subtract: Enter s

<First point>/Object/Add: Enter o

(SUBTRACT mode) Select objects: Select the circle

Area = 0.02, Circumference = 0.46

Total area = 0.32

(SUBTRACT mode) Select objects: Select the other circle

Area = 0.02, Circumference = 0.46

Total area = 0.30

(SUBTRACT mode) Select objects: Press ENTER

<First point>/Object/Add: Press ENTER