Based on the diagram, which expresses all possible lengths of segment ab? ab = 25 27 < ab < 81 ab = 85 ab< 27 or ab > 81

The answer

according to the figure, we can solve this problem only by applying sines rule:
that is 
sinA/a  = sinB/b = sinC /c

As we observe,  sin A /54  = sin B/27 = sin C/ c, and c = AB

besides, sinC > sinB > sinA  , so the only answer possible is 
27 < AB < 81 

we know that

The sum of the lengths of any two sides of a triangle is greater than the length of the third side (Triangle Inequality Theorem)

So

see the attached figure to better understand the problem

1)

2)

3)

therefore

the answer is the option

4+2=-2. 1+2=3. y=-2/3x+b. 2=4/3+b. 2/3=b. the answer is y= -2/3x+2/3

5/ 1/3=15 i think sorry if im wrong