Help me with this please

Show this is false:  For each non-zero integer x there exists integer y such that xy=1

Let's take x=2, so our equation is

2y = 1

That has solution y=1/2 which isn't an integer, not in Z*.  There's no integer y that can solve this equation.  We found an x where the y doesn't exist, that's a counterexample to the claim.

which expression can be used to convert 80 us dollars (usd) to australian dollars (aud)?

1 usd = 1.0343 aud

1 aud = 0.9668 usd

step-by-step explanation:

sorry just need the points

step-by-step explanation:

use pothagarean therom

a^2+b^2=c^2 so first ac

acm is a right triangle because c= 90°

and am (the hypotenuse or c) =16+9 =25

but there is not enough info we need another angle or side length