Regular triangular pyramid

Calculate the volume and surface area of the regular triangular pyramid. The height of the pyramid is 12 centimeters. The bottom edge is 4 centimeters, and the height of the sidewall is 12 centimeters.

Correct answer:

V =  96 cm³
S =  96 cm²

Step-by-step explanation:

$$\begin{gathered} h=12\text{cm} \\ a=4\text{cm} \\ {h}_2=12\text{cm} \\ {S}_1=a\cdot h_2/2=4\cdot 12/2=24{\text{cm}}^2 \\ V=\frac{1}{3}\cdot S_1\cdot h=\frac{1}{3}\cdot 24\cdot 12=96{\text{cm}}^3 \end{gathered}$$

$S=4\cdot S_1=4\cdot 24=96{\text{cm}}^2$

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