Pp=[tex] \frac{a \times h}{2} = \frac{6 \times 8}{2} = 3 \times8 = 24 {cm}^{2} [/tex]
Pb=7*8+7*10+7*6= 56+70+42=168 cm²
Pc =2*Pp+Pb
Pc= 2*24+168=48+168=216cm²
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Pp= [tex] \frac{(a + b) \times h}{2} = \frac{(6 + 12) \times 4}{2} = \frac{18 \times 4}{2} = 9 \times 4 = 36 {cm}^{2} [/tex]
Pb=6*4+12*4+2*5*4= 24+48+40=112cm²
Pc= 2*36+112=72+112=184cm²