Answer: 3
Step-by-step explanation:
Let say x the width of the tank,
x+4 its length,
x+2 its height
[tex]Volume=105=x(x+4)(x+2)\\\\P(x)=x^3+6x^2+8x-105=0\\\\105=3*5*7\\\\P(1)\neq 0\\P(-1)\neq 0\\P(3)=0\\\\\begin{array}{|c|cccc|}&x^3&x^2&x&1\\&1&6&8&-105\\x=3&&3&27&105\\----&--&--&--&--\\&1&9&35&0\\\end{array}\\\\\\P(x)=x^3+6x^2+8x-105=(x-3)(x^2+9x+35)\\And \ x^2+9x+35\ is\ not \ factorizable\ (\Delat=9^2-4*35 < 0)\\[/tex]
width=3
length=3+4=7
height=3+2=5
