Question

find ( mangle b ) and ( ac ).
( mangle b=) ( ) ;
( ac=) ( m )

Explanation:

Step1: Determine the type of triangle

Since two sides \(AB = BC=3m\), the triangle is isosceles. In an isosceles triangle, the angles opposite the equal sides are equal. But here, we can also note that if one angle is \(60^{\circ}\) in a triangle with two equal sides, it becomes equilateral.

Step2: Find \(m\angle B\)

In an equilateral triangle, all angles are \(60^{\circ}\). So \(m\angle B = 60^{\circ}\)

Step3: Find \(AC\)

In an equilateral triangle, all sides are equal. Since \(AB = 3m\) and \(BC = 3m\), then \(AC=3m\)

Answer:

\(m\angle B = 60^{\circ}\); \(AC = 3m\)