Answer:
<h2>
3</h2>
Step-by-step explanation:
Any polynomial can only have as many zeros as is the highest exponent at x.
A cubic polynomial it's: ax³+bx²+cx+d. The highest exponent at x is 3 so it is the largest number of its zeros.
Hopefully this helps: 16(x^2 + 6x + y^2) = 5(8y + 63)
I'm not sure where to take it from there, but hopefully someone can build off of that. :)