Answer:
perimeter of triangle=sum of all three sides
Step-by-step explanation:
[tex]( {2y}^{2} - {2x}^{2} ) + ( {y}^{2} - {x}^{2} + 11 ) \\ + ( {5x}^{2} - {2y}^{2} - 12)[/tex]
[tex] {2y}^{2} + {y}^{2} - {2y}^{2} + {5x}^{2} - {x}^{2} - {2x}^{2} + 11 - 12[/tex]
Hope it helps you<3
[tex] {y}^{2} + {2x}^{2} - 1[/tex]
