Luas bidang datar tersebut adalah... cm2 a. 54 b. 60 c. 68 d. 72

alas = 12 - 8 = 4 cm

sisi miring
[tex]sisi \: miring = {4}^{2} + {4}^{2} \\ = 16 + 16 \\ = \sqrt{32} \\ = \sqrt{16 \times 2} \\ = 4 \sqrt{2} [/tex]
luas trapesium
[tex] \frac{8 + 12}{2} \times 4 \\ = \frac{20}{2} \times 4 \\ = 40 \: {cm}^{2} [/tex]
luas persegi
[tex]l = s \times s \\ = 4 \sqrt{2} \times 4 \sqrt{2} \\ = 16 \times 2 \\ = 32 {cm}^{2} [/tex]
luas keseluruhan
=luas trapesium + luas persegi
[tex] = 40 + 32 = 72 \: {cm}^{2} [/tex]
jawaban D