3 is real 4th roots of 81
The answer would be (-1,2)
240 days is 4 times the half-life, which means that a sample of 1000 mg will decay to

after 240 days.
To find the product of <span>-2x^3+x-5 and x^3-3x-4, we need to multiply each term in the first polynomial by the second polynomial. (So, x^3 - 3x - 4) times ....
-2x^3 = -2x^6 + 6x^4 + 8x^3
x = x^4 - 3x^2 - 4x
-5 = -5x^3 + 15x + 20
If we add all these together, we get (-2x^6 + 7x^4 + 3x^3 - 3x^2 + 11x + 20)</span>
(-36x^4y+144x²y^6) / (-4x²y) =
36xy*(x³+4xy^5) / (-4x²y) =
-9*(x³+4xy^5) / x