+2446 \((2x-y)^2\) represents \(18^2\) . Therefore, in order for there to be a valid value for x and y, \(2x-y=18\) .
Do x=20 and y=2 fit this category? Well, let's see.
\(x=20,y=2;\\ 2*20-2\stackrel{?}{=}18\\ 38\neq 18\)
No, it doesn't. Let's try the next, x=2 and y=20.
\(x=2,y=20;\\ 2*2-20\stackrel{?}{=}18\\ -16\neq 18\)
Ok, x=2 and y=20 are not it. Let's try the next pair.
\(x=10,y=2;\\ 2*10-2\stackrel{?}{=}18\\ 18= 18 \checkmark\)
There we go! We found the pair that works, x=2 and y=20.
