Rosa Pimentel, D. et al. 2026. From Green’s Theorem to the Shoelace Formula: An Application to the Calculation of the Area of the State of Tocantins. Revista Tocantinense de Matemática . 1, 1 (jul. 2026). DOI:https://doi.org/10.20873/retmat.uft.v1n1.2026.23266.