Geometry help asap please it's easy

Question

If CA denotes the circumference of ⨀A and CB denotes the circumference of ⨀B, which equation is true?

Segment d1 is a diameter of ⨀A and segment d2 is a diameter of ⨀B.

d1⋅CA=d2⋅CB

d1⋅CB=d2⋅CA

d1⋅d2=CB⋅CA

CB=d1⋅d2⋅CA

Answer 1

Circumference = pi x diameter

C=pi x d

C/d = pi for any C/d

ratios of circumference to diameter are equal for all circles

CA/d1 = CB/d2 cross multiply to get

d2CA = d1CB that's the 2nd choice

1st choice is false, 3rd & 4th are false

only d2CA=d1CB is correct

2nd choice is d1CB=d2CA which is the same

Answer 2

Hello Raquel!

The formula of he circumference is:

π*d , where d is the diameter

Therefore,

CA = π*d₁

CB = π*d₂

Then,

CA/CB = d₁/d₂

d₁*CB = d₂*CA

Second option