let p1, p2 be Point of (TOP-REAL 2); :: thesis: for a, b, c, d being real number st a < b & c < d & p1 `1 = b & p2 `1 = b & c <= p2 `2 & p2 `2 < p1 `2 & p1 `2 <= d holds
LE p1,p2, rectangle a,b,c,d
let a, b, c, d be real number ; :: thesis: ( a < b & c < d & p1 `1 = b & p2 `1 = b & c <= p2 `2 & p2 `2 < p1 `2 & p1 `2 <= d implies LE p1,p2, rectangle a,b,c,d )
set K = rectangle a,b,c,d;
assume A1:
( a < b & c < d & p1 `1 = b & p2 `1 = b & c <= p2 `2 & p2 `2 < p1 `2 & p1 `2 <= d )
; :: thesis: LE p1,p2, rectangle a,b,c,d
then A2:
p1 `2 >= c
by XXREAL_0:2;
d >= p2 `2
by A1, XXREAL_0:2;
then
( p1 in LSeg |[b,d]|,|[b,c]| & p2 in LSeg |[b,d]|,|[b,c]| )
by A1, A2, JGRAPH_6:10;
hence
LE p1,p2, rectangle a,b,c,d
by A1, JGRAPH_6:71; :: thesis: verum