For calculating any angles, For example, if you like to calculate the angle 'B', enter its known value 'b'. Follow the same step for both 'A' and 'C'.
The calculator follows SSS (Side side side) theorem and uses sine laws for calculating the unknown values for finding the angles. For sides it is same as SAS (side angle side) theorem.
Find the value of a when A = 50°, c = 25 and b = 14.
Cosin law: a2 = b2 + c2 - 2bc cos A
a2 = 142 + 252 - 2 x 14 x 25 x cos50°
a2 = 196 + 625 - 700(0.6427)
a2 = 371.11
Therefore, a = 19.26, which is equal to 19
Find length of largest diagonal of a parallelogram to its nearest integer whose sides of adjacent are c = 45, a = 25cms and its largest parallelogram angle is B = 115°.
Cosine law: b2 = a2 + c2 - 2ac cos B
b2 = 252 + 452 - 2 x 25 x 45 x cos115
b2 = 625 + 2025 - 2250 x (-0.4226)
Here, the cosin of obtuse angle is getting negative so the last term changes its sign.
b2 = 2650 - 2250(-0.4226)
b2 = 2650 + 950.85
b2 = 3600.85
Therefore, b = 60