contestada

Use the diagram of the right triangle above and round your answer to the nearest hundredth.
If m_B = 60° and a = 10 meters, find b.
a 17.32 m
C. 14 m
b. 6.93 m
d. 9.99 m

Respuesta :

Option a: [tex]17.32 \ {m}[/tex] is the length of b

Explanation:

The angle of B is [tex]\angle B=60^{\circ}[/tex] and [tex]a=10 \ m[/tex]

We need to determine the length of b.

First, let us determine the angle of A.

Since, ABC is a triangle, then all the angles add up to 180°

Thus, we have,

[tex]\angle A+\angle B+\angle C=180^{\circ}[/tex]

[tex]\angle A+60^{\circ}+90^{\circ}=180^{\circ}[/tex]

       [tex]\angle A+150^{\circ}=180^{\circ}[/tex]

                   [tex]\angle A=30^{\circ}[/tex]

Thus, the angle of A is [tex]\angle A=30^{\circ}[/tex]

Now, we shall determine the length of b using the sine law formula.

The formula for sine law is given by,

[tex]\frac{a}{\sin A}=\frac{b}{\sin B}[/tex]

where [tex]a=10 \ m[/tex] , [tex]\angle A=30^{\circ}[/tex] , [tex]\angle B=60^{\circ}[/tex]

Thus, we have,

[tex]\frac{10}{\sin 30}=\frac{b}{\sin 60}[/tex]

Simplifying, we get,

[tex]\frac{10}{0.5}=\frac{b}{0.866}[/tex]

Multiplying both sides by 0.866, we get,

[tex]\frac{10\times0.866}{0.5}=b[/tex]

Multiplying the numerator, we have,

[tex]\frac{8.66}{0.5}=b[/tex]

Dividing, we get,

[tex]17.32=b[/tex]

Thus, the length of b is [tex]b=17.32 \ m[/tex]

Hence, Option a is the correct answer.