Respuesta :

SOLUTION

Given the pyramid with a square base in the image, the following are the solution steps wo find the surface area.

Step 1: Describe the formula of the surface area of the pyramid

The pyramid consists of a square base and 4 triangles, therefore the surface area of the pyramid will be the area of the square base added to the areas of the 4 triangles.

Step 2: To get the surface area of the pyramid, we calculate the area of the square base

[tex]\begin{gathered} \text{For the square base} \\ \text{Area}=s^2,s=25\text{ f}eet \\ \text{Area}=25^2=625feet^2 \end{gathered}[/tex]

Step 3: We calculate the area of the 4 triangles

[tex]\begin{gathered} \text{Area}_{\text{triangle}}=\frac{1}{2}bh,\text{ b=25}feet,h=32 \\ \text{Area}_{\text{triangle}}=\frac{1}{2}\times25\times32 \\ \text{Area}_{\text{triangle}}=25\times16=400feet^2 \\ \text{Area of 4 triangles will be 4}\times\text{Area}_{\text{triangle}} \\ \text{Area}_{\text{all traingles}}=4\times400 \\ \text{Area}_{\text{all traingles}}=1600feet^2 \end{gathered}[/tex]

Step 4: Calculate the surface area by following the instruction in Step 1:

[tex]1600+625=2225feet^2[/tex]

Hence, the surface area of the pyramid equals 2225 square feet.

Question b: Surface area of the metal soup can

The metal soup can has the shape of a cylinder, therefore the surface area will be:

[tex]\begin{gathered} SA=2\pi r^2+2\pi r^{}h,r=5,h=20\operatorname{cm} \\ SA=(2\times\pi\times5\times5)+(2\times\pi\times5\times20) \\ SA=157.0796327+628.3185307 \\ SA=785.3981634 \\ SA\approx785.39816\operatorname{cm} \end{gathered}[/tex]

Hence, the surface area of the metal soup can equals 785.39816 square cm.

Question c: Surface area of the ice cream cone with an open top

It can be seen from the image that the height is missing from the cone.

Surafce area of a cone with an open top means we exclude the area of the circular surface:

[tex]\begin{gathered} SA=\pi rl,l=16.6\operatorname{cm},r=\frac{9.4}{2}=4.7\operatorname{cm} \\ SA=\pi\times4.7\times16.6 \\ SA=245.1070588 \\ SA\approx245.107\operatorname{cm} \end{gathered}[/tex]

Hence, the surface area of the ice cream cone can equals 245.107 square cm.

RELAXING NOICE
Relax