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're kidding, right? Urgent homework on Christmas day. What is it - a last minute present for someone?
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 = ........
the area of a rectangle is length times width. so the area of a square is the length of a side squared (since the length and width are equal). thus, the side length of the of a square with area 36 cm^2 is $\displaystyle \sqrt{36} = 6$. so the perimeter is 4 times this length, since the perimeter is the sum of the length of all the sides. thus we get 24