Two circles of radii 5 cm and 4 cm intersect at two points and the distance between their centres is 3 cm. find the length of the common chord.

8 cm

Step-by-step explanation:

Two circles of radii 5 cm and 4 cm intersect at two points D and E.

The distance between their centers (points A and C) is 3 cm.

Consider triangle ACD. In this triangle,

AC = 3 cm (distance between centers)

AD = 5 cm (radius of larger circle)

CD = 4 cm (radius of smaller circle)

So, this is right triangle and therefore, AC is the height of isosceles triangle ADE (triangle ADE is isosceles, because AE = AD).

The height of the isosceles triangle drawn to the base is its median, so CD = CE = 4 cm, hence

DE = 4 + 4 = 8 cm

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional

alright well the answers to your question is

2xy/9 hope this have a nice day : )

step-by-step explanation: