[tex]\\ \sf\longmapsto 4(2 - 3 - 1) + ( - 5)(6) - 7 {}^{2} \\ \\ \longmapsto 4( - 2) + ( - 30) - 7 {}^{2} \\ \\ \sf\longmapsto - 8 - 30 - 49 \\ \\ \sf\longmapsto - 38 - 49 \\ \\ \sf\longmapsto - 87[/tex]