How do i do this ?i need help on finding the answer . To all three questions

area of larger circle : 9π = 28.27

area of smaller circle: 4π = 12.57

area of shaded region: 15.71

Step-by-step explanation:

area of a circle = πr^2

I think these are right i dont know tho

assuming you mean addition: addition and subtraction are reverse operations.

step-by-step explanation:

it's equivalent, so we can say that its equal.

let's call the denominator x and the numerador is 18 less then denominator, x - 18.

multiply

2.x = 5.(x - 18)

2x = 5x - 90

90 = 5x - 2x

90 = 3x

x = 90/3

x = 30

so: