式12: polygon left parenthesis, "O" , "A" , "A" plus "B" , "B" , right parenthesispolygonO,A,A+B,B
12
式13: polygon left parenthesis, "O" , left parenthesis, 0 , "B" . "y" , right parenthesis , "B" , right parenthesispolygonO,0,B.y,B
13
式14: polygon left parenthesis, "A" , "A" plus "B" , "A" plus left parenthesis, "B" . "x" , 0 , right parenthesis , right parenthesispolygonA,A+B,A+B.x,0
14
式15: polygon left parenthesis, "B" , "A" plus "B" , "B" plus left parenthesis, 0 , "A" . "y" , right parenthesis , right parenthesispolygonB,A+B,B+0,A.y
15
式16: polygon left parenthesis, "O" , "A" , left parenthesis, "A" . "x" , 0 , right parenthesis , right parenthesispolygonO,A,A.x,0
16
式17: polygon left parenthesis, left parenthesis, 0 , "B" . "y" , right parenthesis , "B" , "B" plus left parenthesis, 0 , "A" . "y" , right parenthesis , left parenthesis, 0 , "A" . "y" plus "B" . "y" , right parenthesis , right parenthesispolygon0,B.y,B,B+0,A.y,0,A.y+B.y
17
式18: polygon left parenthesis, left parenthesis, "A" . "x" , 0 , right parenthesis , "A" , "A" plus left parenthesis, "B" . "x" , 0 , right parenthesis , left parenthesis, "A" . "x" plus "B" . "x" , 0 , right parenthesis , right parenthesispolygonA.x,0,A,A+B.x,0,A.x+B.x,0
