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Solving a linear inequality follows the same steps as an equation, with one crucial difference: multiplying or dividing by a negative number reverses the direction of the inequality.
Linear inequality
ax + b < c ⇒ x < (c − b)/a if a > 0, and x > (c − b)/a if a < 0
−2x < 6, and dividing by −2 flips the sign to give x > −3.
Multiplying by a negative reflects the number line, so the order of any two values is reversed.