solve the inequality 1 - 3x ≤ 7

Add 3x to both sides

1 ≤ 7 + 3x

Subtract 7 from both sides

-6 ≤ 3x

Divide both sides by 3

-2 ≤ x

This says x must be greater than or equal to -2, so it can also be written as x ≥ -2

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