Apackage has 5 erasers number of packages 6 total number of erasers

Let r = 3. what is the value of r + 58?

Let f(x) = 5/x and g(x)=2x2+5x. what two numbers are not in the domain of f o g

I’ve been trying all day to figure this puzzle out. i need the work for it aswell. it is a factoring polynomials tarsia. the image is below.