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Help I'm practicing

User Bilgin
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1 Answer

1 vote

120 cm²

1) Let's calculate the surface area by calculating each polygon's area. In this polygon we have, considering that this is a building block

2 triangles 4x3


\begin{gathered} S=(1)/(2)\cdot b\cdot h \\ S=(1)/(2)\cdot4\cdot3=6cm^2 \end{gathered}

2 triangles = 12 cm²

1 rectangle 6 x 9:


S=6\cdot9=54cm^2

1 rectangle 5 x 9


S=5\cdot9=45cm^2

1 rectangle 3 x 9


S=3\cdot9=36\operatorname{cm}

2) Adding it all up: 12 cm²+54+45+27 = 120 cm²

Help I'm practicing-example-1
User PiotrK
by
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