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📐 Law of Sines & Law of Cosines

Just 2 angles and 1 side tell you
the whole triangle

It doesn't need to be a right triangle. When you know angle-angle-side, use the law of sines; when you know side-angle-side, use the law of cosines — either way, you can find every remaining side and angle. Change the triangle with sliders and see how both laws work.

Set angle A, angle B, and side a (the side opposite angle A), and the triangle is completely determined. Use the law of sines a/sinA = b/sinB = c/sinC = 2R to find the remaining sides and even the radius R of the circumscribed circle.
Angle A50°
Angle B70°
Side a (opposite angle A)8