In the following figure, the circles with centres B and D have radii 4 cm and xcm, respectively. AC is a tangent to both the circles. Find the value of x.

Radius of two circles r₁ = 4cm 

                                   r₂= x cm 

Concept Used: ​

Similar triangle property;

When two triangles are similar, than ratios of their respective sides are equal.

 Solution:

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