Example

Solving 8n4=2n+68n - 4 = -2n + 6 by Collecting Variables and Constants

To solve 8n4=2n+68n - 4 = -2n + 6, notice that variable terms (8n8n and 2n-2n) and constant terms (4-4 and 66) appear on both sides of the equation. Because 8>28 > -2, designate the left side as the variable side and the right side as the constant side.

Step 1 — Remove the variable term from the constant side: The term 2n-2n is on the constant side, so add 2n2n to both sides using the Addition Property of Equality:

8n+2n4=2n+2n+68n + 2n - 4 = -2n + 2n + 6

Combine like terms: 10n4=610n - 4 = 6. Now the variable appears only on the left.

Step 2 — Remove the constant from the variable side: The constant 4-4 is on the variable side, so add 44 to both sides:

10n4+4=6+410n - 4 + 4 = 6 + 4

10n=1010n = 10

Step 3 — Isolate the variable using the Division Property of Equality: Because nn is multiplied by the coefficient 1010, divide both sides by 1010:

10n10=1010\frac{10n}{10} = \frac{10}{10}

n=1n = 1

Step 4 — Check by substitution: Replace nn with 11 in the original equation:

8(1)4=?2(1)+68(1) - 4 \stackrel{?}{=} -2(1) + 6

84=?2+68 - 4 \stackrel{?}{=} -2 + 6

4=44 = 4 \checkmark

Because both sides are equal, n=1n = 1 is confirmed as the correct solution. Unlike the earlier examples that used the Subtraction Property to collect terms, this equation requires the Addition Property in both collecting steps — adding 2n2n to eliminate the negative variable term from the right side, and adding 44 to eliminate the negative constant from the left side. Additionally, a final division step is needed because the combined coefficient (1010) is not equal to 11.

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Updated 2026-04-21

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