Zinc has a density of 0.258 lb/in³ (pounds per cubic inch).
darius is making a pyramid out of solid zinc. the pyramid has a square base 6 inches on each side, and a height of 2.5 inches.
how many pounds of zinc does he need?
do not round final !

For this case, we have that by definition:

ρ =

Where:

ro: Density

M: Mass

V: Volume

We find the volume of the pyramid:

Where:

: Represents the area of the base of the square pyramid

h: Represents the height

So:

We have to:

M = ρ* V

So, you need 7.74 pounds of zinc

7.74 pounds

x intercept = (-1,0)   (4,0)

225x²+4=0

225x²=0-4

225x²=-4

x²=-4/225

x=±√-4/225