Answer:
128√5/3 mm³
Step-by-step explanation:
Since we are not told what to find, we can as well look for the volume of the pyramid
Volume of a square pyramid: V = (1/3)a²h
a is the side length of the square
h is the height of the pyramid
Given
a = 8mm
l² = (a/2)² + h²
l² = (a/2)² + h²
6² = (8/2)² + h²
h² = 6² - 4²
h² = 36 - 16
h² = 20
h = √20
Volume of a square pyramid = (1/3)*8²*√20
Volume of a square pyramid = 1/3 * 64 * 2√5
Volume of a square pyramid = 128√5/3 mm³
Answer:
length = 5
width = 9
Step-by-step explanation:
V = lwh
let 'x' = length
let '4+x' = width
9 = height
405 = 9x(4+x)
405 = 36x + 9x²
this is a quadratic equation: 9x² + 36x - 405 = 0
factor out a 9 to get:
9(x² + 4x - 45) = 0
9(x-5)(x+9) = 0
one root is 5 and the other is -9
since distance cannot be negative we use 5 as the length and 9 is the width
