When x=2, we have (x+2−x)(2−x−2)=(2+2−2)(2−2−2)=(2)(−2)=−4.
Alternatively, we could simplify (x+2−x)(2−x−2) to obtain (2)(−x) or −2x and then substitute x=2 to obtain a result of −2(2) or −4.
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