Question

Okay, another question! Im so sorry if this is annoying. Also please no joke answers, and if possible please explain so I can understand!

Answer 1

Uhhh rain made a mistake

Answer 2

Rain made an error.

The expression should be
`3\left((1)/(2)*10* \bf{12}\right)+ \left((1)/(2)*10 * 8.7\right)`

Note the term in bold which is 12. I've replaced 13 with this value. This is because the height of each lateral side is 12 inches, instead of 13 inches.

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The steps needed to be taken are therefore:

`3\left((1)/(2)*10* 12\right)+ \left((1)/(2)*10 * 8.7\right)\\\\\\3\left(5* 12\right)+ \left(5 * 8.7\right)\\\\\\3\left(60\right)+ 43.5\\\\\\180+ 43.5\\\\\\223.5\\\\\\`

This means the triangular pyramid's surface area should be 223.5 square inches.