<-- Angle A
<-- Side a
<-- Angle B
<-- Side b
<-- Side C

a2 + b2 = c2

a2 = c2 - b2

a = √c2 - b2
a = √202 - 162
a = √400 - 256
a = √144
a = 12

## Calculate Angle A:

 sin(A)  = OPPOSITE HYPOTENUSE

 sin(A)  = a c

 sin(A)  = 12 20

Sin(A) = 0.6
Angle A = 36.8699°

## Calculate Angle B:

 sin(B)  = OPPOSITE HYPOTENUSE

 sin(B)  = b c

 sin(B)  = 16 20

Sin(B) = 0.8
Angle B = 53.1301°

 inradius  = ab a + b + c

 inradius  = (12)(16) 12 + 16 + 20

Angle A = 36.8699
Angle B = 53.1301
Side A = 12
Side B = 16
Side C = 20

Angle A = 36.8699
Angle B = 53.1301
Side A = 12
Side B = 16
Side C = 20
##### How does the Right Triangles Calculator work?
Free Right Triangles Calculator - This solves for all the pieces of a right triangle based on given inputs using items like the sin ratio, cosine ratio, tangent ratio, and the Pythagorean Theorem as well as the inradius.
This calculator has 5 inputs.

### What 1 formula is used for the Right Triangles Calculator?

a2 + b2 = c2

For more math formulas, check out our Formula Dossier

### What 8 concepts are covered in the Right Triangles Calculator?

cos
cos(θ) is the ratio of the adjacent side of angle θ to the hypotenuse
a radius of an inscribed circle or sphere
pythagorean theorem
a fundamental relation in Euclidean geometry among the three sides of a right triangle. It states that the area of the square whose side is the hypotenuse is equal to the sum of the areas of the squares on the other two sides
a2 + b2 = c2
ratio
indicates how many times one number contains another
right triangles
sin
sin(θ) is the ratio of the opposite side of angle θ to the hypotenuse
tangent
the straight line that just touches the curve at that point
triangle
a flat geometric figure that has three sides and three angles