Answer
$-7y^{2}-3x$
Work Step by Step
We are asked to subtract $(8y^{2}+4x)$ from $(y^{2}+x)$. This is equivalent to $(y^{2}+x)-(8y^{2}+4x)$.
To subtract two polynomials, add the opposite of the second polynomial to the first polynomial.
$(y^{2}+x)+(-8y^{2}-4x)$
Next, we can combine like terms.
$(y^{2}-8y^{2})+(x-4x)=-7y^{2}-3x$
