Step-by-step explanation:
In the following triangle, a= ? , b= 2cm.
m<B= 105° , m<C = 15° ,m< A =?
Now, we know that sum of the interior angles of the triangle = 180°
m<B+m<C +m< A =180°
105°+15°+m< A=180°
m< A= 180- 120° = 60°
[tex] \frac{ \sin( A) }{a} = \frac{ \sin(B) }{b} [/tex]
[tex] \frac{ \sin(60) }{a} = \frac{ \sin(105) }{2} [/tex]
[tex]a = \frac{ \sin(60) }{ \sin(105) } \times 2[/tex]
[tex]a = 1.79[/tex]
[tex]a = 1.8[/tex]
