Find the radius of the circle angle 90 A=20cm2

not sure if thets how you do it tho

Step-by-step explanation:

Given, radius, r=20 cm, central angle, θ=90o, π=3.14

Area of sector =360oθ×πr2

                        =360o90o×3.14×20×20

                        =41×100314×20×20

                        =314

∴ the area of sector is 314 cm2.

Step-by-step explanation:

I think you missed some things when posting the problem description.

did you mean to find the radius of a circle segment of 90 degrees and an area of 20 cm² ?

if that is the case :

remember, the area of a circle (a full circle of 360 degrees)

A = pi×r²

again, this is for the full 360 degrees.

how big is the area then for only a part of the circle ?

simply, it is the ratio of the angle of the segment compared to the total 360 degrees.

so,

As = pi×r² × angle/360

we have here

As = 20

angle = 90

20 = pi×r² × 90/360 = pi×r² × 1/4

80 = pi×r²

r² = 80/pi

r = sqrt(80/pi) = sqrt(16×5/pi) = 4×sqrt(5/pi) =

= 5.046265044 cm ≈ 5.05 cm

mr. flanders’ class sold 47 doughnuts and   mr. rodriquez’s class sold 38 cartons of milk

step-by-step explanation:

let x be the number of doughnuts sold by mr. flanders’ class and y be the number of cartons sold by mr. rodriquez’s class.

1. together, the classes sold 85 items, then

x+y=85.

2. both classes earn earned $104.49 for their school. if doughnuts were sold for $1.35 each, then x doughnuts costed $1.35x. if cartons of milk were sold for $1.08 each, then y cartons costed $1.08y. hence,

1.35x+1.08y=104.49.

3. solve the system of two equations: