Isosceles Triangle Calculator
Find equal sides, area and perimeter from the base and perpendicular height of an isosceles triangle.
Formula
s = √[(b/2)² + h²]; A = bh/2; P = b + 2s.
Base b: 6 cm · Perpendicular height h: 4 cm · Each equal side ≈ sqrt(((6 cm × 0.01 m/cm)÷2)^2+(4 cm × 0.01 m/cm)^2)×100 · Area ≈ (6 cm × 0.01 m/cm)×(4 cm × 0.01 m/cm)×5000 · Perimeter ≈ (6 cm × 0.01 m/cm)×100+2×(5)
How to use
- Enter the base length.
- Enter the perpendicular height and units.
- Read the equal side, area and perimeter.
Examples
- Base 6 cm and height 4 cm give sides 5 cm, area 12 cm² and perimeter 16 cm.
Frequently asked questions
Where is the height measured?
From the vertex between equal sides, perpendicular to the base.
Why is the base halved?
The altitude of an isosceles triangle bisects its base.
Can I mix units?
Yes. Lengths are converted before calculation; results use cm and cm².
Sources
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