What you need to know for this case is that the sum of the internal angles of a triangle is 180 ° We then have the following equation that is given by: (2x) + (3x) + (4x) = 180 Clearing x we have: 9x = 180 x = 180/9 x = 20 Therefore we have: m∠A = (40) ° m∠B = (60) ° m∠C = (80) ° Answer: B) m∠B = 60 °
