Answer:
D
Step-by-step explanation:
There can be infinite solutions
Answer:
Step-by-step explanation:
By applying the concept of calculus;
the moment of inertia of the lamina about one corner 
is:
where :
(a and b are the length and the breath of the rectangle respectively )
![I_{corner} = \rho [\frac{bx^3}{3}+ \frac{b^3x}{3}]^ {^ a} _{_0}](https://tex.z-dn.net/?f=I_%7Bcorner%7D%20%3D%20%20%5Crho%20%5B%5Cfrac%7Bbx%5E3%7D%7B3%7D%2B%20%5Cfrac%7Bb%5E3x%7D%7B3%7D%5D%5E%20%7B%5E%20a%7D%20_%7B_0%7D)
![I_{corner} = \rho [\frac{a^3b}{3}+ \frac{ab^3}{3}]](https://tex.z-dn.net/?f=I_%7Bcorner%7D%20%3D%20%20%5Crho%20%5B%5Cfrac%7Ba%5E3b%7D%7B3%7D%2B%20%5Cfrac%7Bab%5E3%7D%7B3%7D%5D)
Thus; the moment of inertia of the lamina about one corner is
The formula for the area of a triangle is 1/2*base*height so setting a=18 you can set up the equation as 18=1/2*b*h which gives 18=1/2*(c-1)*6c. simplifying gives 18=3c(c-1). setting the equation to 0 gives a quadratic which is
3c^2-3c-18=0 which gives c= 3 or -2 since -2 doesnt make sense we can assume c=3 so filling the equation with c=3 gives 18=1/2*(6*3)*(3-1) which gives 18=1/2(18)(2) you see 1/2*2 cancels and you are left with 18=18 which is correct so c=3 and height =18
