$1\mathrm{.}10$: A Predicate on Booleans

Define the predicate ITE$($x$,$ y$,$ z$)$ to be true if and only if either x is true and y is true, or x is false and z is true. $($The name $$ITE$$ stands for $$if$-$then$-$else$.)$ Then the predicates ITE$($x$,$ x$,$ x$)$ and ITE$($y$,$ y$,$ y$)$ always have the same value, whatever the values of x and y might be$.$