45-45-90 triangle calculator
Calculate the equal legs, hypotenuse and area of an isosceles right triangle from one leg.
Formula
Other leg = a; hypotenuse = a√2; area = a²/2; a in cm.
Known leg: 5 cm · Other leg ≈ (5 cm × 0.01 m/cm)×100 · Hypotenuse ≈ (5 cm × 0.01 m/cm)×sqrt(2)×100 · Area ≈ (5 cm × 0.01 m/cm)^2÷2×10000
How to use
- Enter one leg, not the hypotenuse.
- Choose its length unit.
- Read sides in cm and area in cm².
Examples
- Leg 5 cm gives area 12.5 cm².
Frequently asked questions
Are the two legs equal?
Yes. Equal 45° angles have equal opposite sides.
What if I know the hypotenuse?
Divide it by √2 to obtain the leg first.
Is this half a square?
Yes. A diagonal cuts a square into two 45°–45°–90° triangles.
Sources
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