Question

All edges of a square pyramid are 18cm.what is it's volume.?​

Answer 1

Step-by-step explanation:

volume of a square volume is 1/3*base area * height

Answer 2

$972 \sqrt{2} \: {cm}^{3}$

Step-by-step explanation:

$Given, \: \: \: all \: \: edges = 18 \: cm \\ we \: \: know \: \: \boxed{ volume \: \: of \: \: pyramid = \frac{1}{3} \times area \: \: of \: \: base \times heigth } \\ Now, \: \: heigth = \sqrt{ ({18})^{2} - ( \frac{18 \sqrt{2} }{2})^{2} } \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: = \sqrt{324 - 162} \\ \: \: \:= \sqrt{162} \\ \: \: \: \: \: \: \: \: = 9 \sqrt{2} \: cm \\ so, \: \: volume \: \:of \: \: square \: \: pyramid= \frac{1}{3} \times {18}^{2} \times 9 \sqrt{2} \\ \: \: \: \: \: \: \: \: \: \: = 972 \sqrt{2} \: {cm}^{3}$