Answer:
C= 2 radians.
Step-by-step explanation
Length of arc = r C where r = the radius and C is the angle in radians.
Area of the sector = 1/2 r^2 C
So we have:
30 = rC and
900 = 1/2 r^2 C
From the first equation we have r = 30/C so substituting for r:
900 = 1/2 (30/C)^2 * C
900 = 0.50 (900/C^2) * C
900 = 450/C
C= 2 radians.