(PLEASE HELP!) The central angle of a sector is 72 degrees and the sector has an area of 15.71. Find the radius.

The radius is 5 units (approximately)

Step-by-step explanation: The area of a sector with central angle X is given as;

Area = (X/360) x pi x r^2

Since the area has been given as 15.71 units, we can input the known values into the formula as follows;

15.71 = (72/360) x 3.14 x r^2

By cross multiplication we now have

(15.71/3.14) = 1/5 x r^2

(15.71/3.14) x 5 = r^2

78.55/3.14 = r^2

25.0159 = r^2

Add the square root sign to both sides of the equation

5.001 = r

The radius is equal to 5 units (approximately)

f(x) = - 2/3x + 5; f(5/2)

substitute 5/2 in for x:

f(5/2) = -2/3(5/2) + 5

simplify the right side:

f(5/2) = -5/3 + 5

f(5/2) = 10/3

answer:

f(5/2) = 10/3

i hope this you!