Inequality Solver
Solve a linear inequality a·x + b (op) c for x, with automatic sign-flip detection.
How it works
- 1Enter the coefficient a, constant b, an inequality operator, and the right-hand side c to express a·x + b (op) c.
- 2The solver isolates x by subtracting b from both sides and dividing by a — flipping the operator automatically when a is negative.
- 3If a = 0 the expression is constant: the result is either all real numbers (always true) or no solution (always false).
Use cases
- Checking homework solutions for one-variable linear inequalities.
- Setting up feasibility constraints in budgeting or scheduling problems.
- Teaching students how dividing by a negative coefficient flips the inequality sign.
Frequently asked questions
Why does the inequality symbol flip?
Multiplying or dividing both sides of an inequality by a negative number reverses the order of the number line, so the direction of the inequality must flip to keep the statement true.
What happens when a = 0?
With a = 0 there is no x term; the inequality reduces to b (op) c, a statement that is either always true (all real numbers) or always false (no solution).
Does this handle strict and non-strict inequalities?
Yes — choose < or > for strict inequalities (open boundary) and ≤ or ≥ for non-strict (closed boundary). The boundary value is the same; only inclusion of the endpoint differs.
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