The nth term of a sequence is 3n squared divided by 2 what is the second term of the sequence?

Arley is building a model of a city map. in one part of the city, three roads form a right triangle, which harley draws as triangle abc, with the following measures: m∠b=90° and m∠a=30°. in his scale model, the hypotenuse of triangle abc, ac¯¯¯¯¯¯¯¯, has a length of 817−−√ cm. what is the value of a (the length of bc¯¯¯¯¯¯¯¯)?

Thelime contains the point(-3,0) and parallel x-3y=3( show all work)

The anwser cause i do not understand just plez