Triangle Inequality Checker
How It Works
This triangle inequality checker uses established formulas to provide accurate results.
The basic rule:
- a + b > c
- a + c > b
- b + c > a
- Right test: a² + b² = c²
Results are estimates. Consult a professional for critical decisions.
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Explore Allday Everyday Math →Frequently Asked Questions
What is the triangle inequality theorem?
The triangle inequality theorem states that the sum of any two sides of a triangle must be greater than the third side. All three combinations must be checked: a+b > c, a+c > b, and b+c > a.
What is the difference between scalene, isosceles, and equilateral?
A scalene triangle has no equal sides, an isosceles triangle has exactly two equal sides, and an equilateral triangle has all three sides equal.
How can I tell if a triangle is acute, right, or obtuse?
Sort the sides so a ≤ b ≤ c. If a² + b² = c², it is a right triangle. If a² + b² > c², it is acute. If a² + b² < c², it is obtuse.
Can three equal lengths form a triangle?
Yes, three equal positive lengths always form an equilateral triangle. For example, sides 5, 5, 5 satisfy 5+5 > 5 in all combinations.