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Algebra Difficulty 1.8 Junior Find the answer

If n=7 n = 7 , which of the following expressions is equal to an even integer: 9n,n+8,n2,n(n−2),8n 9n, n+8, n^2, n(n-2), 8n ?

A number or a short expression. Spacing and $ signs are ignored.

Solution

When n=7 n=7 , we have 9n=63,n+8=15,n2=49,n(n−2)=35,8n=56 9n=63, n+8=15, n^2=49, n(n-2)=35, 8n=56 . Therefore, 8n 8n is even. For every integer n n , the expression 8n 8n is equal to an even integer.

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