Answer:
[tex]\large\boxed{a=4\sqrt3}[/tex]
Step-by-step explanation:
We have the triangle 30° - 60° - 90°. In that triangle sides are in proportion
1 : √3 : 2 (look at the picture).
We have
[tex]a\sqrt3=12[/tex] multiply both sides by √3 (use √a · √a = a)
[tex]3a=12\sqrt3[/tex] divide both sides by 3
[tex]a=4\sqrt3[/tex]
[tex]b=2a\to b=2(4\sqrt3)=8\sqrt3[/tex]
