Let's solve for x using trigonometric relation ( Cos )
we know,

now



hence, the value of x is 
378x^3 , i think thats right.
okay so first you do 6 times 2 you got 12 so maybe 2.5 times 6 and that is 15 so now you multiply 4.5 times 2.5 and i got 11.25. So 11.25 pounds of chicken is needed.