Triangle Theorems Calculator

Free online Triangle calculator calculates undefined values from triangles for AAA, ASA, SAS, AAS and SSS in radius, degrees formats using Triangle Theorems.

AAA Triangle Calculator

ASA Triangle Calculator

SAS Triangle Calculator

AAS Triangle Calculator

SSS Triangle Calculator

AAA (angle, angle, angle) Formula:

C = 180 - A - B

ASA (angle, side, angle) Formula:

    C = 180 - A - B
    a = (c * sin(A)) / sin(C)
    b = (c * sin(B)) / sin(C)
    s (used to find K) = (a+b+c)/2
    K = √(s*(s-a)(s-b)(s-c))
    P = a + b + c

SAS (side, angle, side) Formula:

    b = √(c2 + a2 - 2bc*cos(A))
    A = arccos(b2 + c2 - a2)/2bc
    C = 180 - A - B
    s (used to find K) = (a+b+c)/2
    K = √(s*(s-a)(s-b)(s-c))
    P = a + b + c

AAS (angle, angle, side) Formula:

    C = 180 - A - B
    b = (a * sin(B)) / sin(A)
    c = (a * sin(C)) / sin(A)
    s (used to find K) = (a+b+c)/2
    K = √(s*(s-a)(s-b)(s-c))
    P = a + b + c

SSS (side, side, side) Formula:

    A = arccos(b2 + c2 - a2)/2bc
    B = arccos(c2 + a2 - b2)/2bc
    C = 180 - A - B
    s (used to find K) = (a+b+c)/2
    K = √(s*(s-a)(s-b)(s-c))
    P = a + b + c