Please help me to solve the following problem.
A sector of a circle of radius r cm contains an angle of 1.2 radians. Given that the sector has the same perimeter as a square of area 36 cm^2, find the value of r.
You should get that the perimeter of the square is 24 cm.
You should have a formula for arclength. Use it. The perimeter of the sector will be arclength + 2r = (.....) r.
Then 24 = (.....) r => r = ........