2=10/5-2 is this a solution?

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

1- what do you think the product of a nonzero rational number and an irrational number is? is it rational or irrational? make use of variables, the closure property of integers, and possibly a proof by contradiction to prove your hypothesis.2- why do we have to specify that the rational number must be nonzero when we determine what the product of a nonzero rational number and an irrational number is? if the rational number were 0, would it give us the same result we found in the first question?

Show your workcan a right triangle have this sides? *how to prove it without using the pythagorean theorema*