If n=7, which of the following expressions is equal to an even integer: 9n,n+8,n2,n(n−2),8n?
A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.
Solution
When n=7, we have 9n=63,n+8=15,n2=49,n(n−2)=35,8n=56. Therefore, 8n is even. For every integer n, the expression 8n is equal to an even integer.
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