Plz help me. i don’t want to fail math. ahahahah

What is the value of x in the diagram below?

F(x)=x/2-2 and g(x)=2x^2+x-3 find (f+g)(x)

Is the product of two rational numbers irrational or rational? first, make a hypothesis by multiplying two rational numbers. then, use variables such as x=a/b and y=c/d and the closure property of integers to prove your hypothesis.