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I need help to find the surface area. I will send a clear photo.

I need help to find the surface area. I will send a clear photo.-example-1
User Manan Shah
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1 Answer

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To calculate the surface area of the object on the picture, you have to calculate the area of each face and then add them together.

The figure has 6 faces, each face is quadrilateral and the opposite faces are equal, which means that the shape has 3 pairs of congruent faces.

1. The top and bottom faces are rectangular, with length l=11cm and width w=16cm.

To determine the area of these faces you have to multiply the length by the width:


A=l\cdot w

Since both faces are equal, you have to multiply it by 2:


\begin{gathered} 2A=2(lw) \\ 2A=2(11\cdot16) \\ 2A=2\cdot176 \\ 2A=352\operatorname{cm}^2 \end{gathered}

2. The front and back faces are parallelograms with base b=11cm and height h=6.7cm.

To determine the area of a parallelogram you have to multiply its base by its height:


A=b\cdot h

As before, both faces are equal, to determine the area of both, multiply the area by 2:


\begin{gathered} 2A=2(bh) \\ 2A=2(11\cdot6.7) \\ 2A=2\cdot73.7 \\ 2A=147.4\operatorname{cm}^2 \end{gathered}

3. The remaining faces are rectangular with width w=16cm and height h=7cm.

To determine the area you have to multiply the width by the height:


A=w\cdot h

Once again, since there are two equal faces, you have to multiply the area by 2:


\begin{gathered} 2A=2(wh) \\ 2A=2(16\cdot7) \\ 2A=2\cdot112 \\ 2A=224\operatorname{cm}^2 \end{gathered}

Now that the area of all 6 faces of the shape is determined, you have to add them:


\begin{gathered} SA=352+147.4+224 \\ SA=723.4\operatorname{cm}^2 \end{gathered}

The surface area of the shape is 723.4cm²

User Shivam Roy
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