Question

in an oblique triangle ABC, A = 45 degrees, C = 72 degrees, what is the measure of angle B?​

Answer 1

Answer:

∠B = 63°

Step-by-step explanation:

Sum of all internal angles in a triangle = 180° (Angle Sum Property of a triangle)

∠A + ∠B + ∠C = 180°

substituting given values of ∠A and ∠C,

45° + ∠B + 72° = 180°

=> ∠B = 180° - (45° + 72°)

=> ∠B = 180° - 117°

∴ ∠B = 63°

Answer 2

In every sort of triangle, the measure of three internal angles equals 180°

In ∆ABC, A = 45 degrees, C = 72 degrees

Therefore, Angle B= 180° - ( A° + C°)

= 180° - ( 45° + 72°)

= 180° - 117°

= 63°

Hence, Angle B= 63°