Answer:
b=4.9
C. is the correct option.
Step-by-step explanation:
In triangle TGN,
Let <RTG be x
cosx= b/h
or, cosx = 2/a
Again,
In triangle TRG,
cosx = b/h
(for bigger right angled triangle)
cosx = a/(4+2)
cosx = a/6
Now
cosx = 2/a = a/6
or, 2/a = a/6
or, 12 = a²
so, a² = 12
Now,
For TRG,
h² = p²+b²
or, 6² = b² + a²(a²=12)
or, 6² = b² + 12
or, 36 = b² + 12
or, 36 -12 = b²
or, b² = 24
or, b = square root 24
so, b = 4.8989
so, b = 4.9
