let G be V9() Matrix of (TOP-REAL 2); :: thesis: ( G is X_equal-in-line implies v_strip (G,(len G)) = { |[r,s]| where r, s is Real : (G * ((len G),1)) `1 <= r } )

0 <> width G by MATRIX_0:def 10;

then A1: 1 <= width G by NAT_1:14;

assume G is X_equal-in-line ; :: thesis: v_strip (G,(len G)) = { |[r,s]| where r, s is Real : (G * ((len G),1)) `1 <= r }

hence v_strip (G,(len G)) = { |[r,s]| where r, s is Real : (G * ((len G),1)) `1 <= r } by A1, GOBOARD5:9; :: thesis: verum

0 <> width G by MATRIX_0:def 10;

then A1: 1 <= width G by NAT_1:14;

assume G is X_equal-in-line ; :: thesis: v_strip (G,(len G)) = { |[r,s]| where r, s is Real : (G * ((len G),1)) `1 <= r }

hence v_strip (G,(len G)) = { |[r,s]| where r, s is Real : (G * ((len G),1)) `1 <= r } by A1, GOBOARD5:9; :: thesis: verum