[tex] > resolucao \\ \\ \geqslant teorema \: de \: pitagoras \\ \\ d {}^{2} = a {}^{2} + b {}^{2} \\ 15 {}^{2} = 12 {}^{2} + b {}^{2} \\ 225 = 144 + b {}^{2} \\ b {}^{2} = 225 - 144 \\ b {}^{2} = 81 \\ b = \sqrt{81} \\ b = 9 \\ \\ \\ = = = = = = = = = = = = = = = = = = = = = \\ \\ \\ a = b \times h \\ \\ a = 9 \times 12 \\ \\ a = 108cm {}^{2} \\ \\ \\ resposta \: > \: \: letra \: ( \: \: \: d \: \: \: ) \\ \\ \\ \geqslant \leqslant \geqslant \leqslant \geqslant \leqslant \geqslant \leqslant \geqslant [/tex]