Respuesta :

Answer:

m∠B = 100°

a = 4.6

b = 7.36

Step-by-step explanation:

By applying sine rule in the given triangle,

[tex]\frac{\text{sin(A)}}{a}= \frac{\text{sin(B)}}{b}= \frac{\text{sin(C)}}{c}[/tex]

Now substitute the values in the expression,

[tex]\frac{\text{sin(38)}}{a}= \frac{\text{sin(B)}}{b}= \frac{\text{sin(42)}}{5}[/tex]

[tex]\frac{\text{sin(38)}}{a}= \frac{\text{sin(42)}}{5}[/tex]

[tex]a=\frac{5\text{sin(38)}}{\text{sin(42)}}[/tex]

a = 4.6

By applying triangle sum theorem in ΔABC,

m∠A + m∠B + m∠C = 180°

38° + m∠B + 42° = 180°

m∠B = 180° - 80°

m∠B = 100°

[tex]\frac{\text{sin(100)}}{b}= \frac{\text{sin(42)}}{5}[/tex]

[tex]b=\frac{5\text{sin(100)}}{\text{sin(42)}}[/tex]

b = 7.36