If two circles have radii 10 cm and 15cm and they touch each other. Find the distance between their centres.

If two circles have radii 10 cm and 15cm and they touch each other. Fi

1.	If two circles have radii 10 cm and 15cm and they touch each other. Find the distance between their centres.
Answer» Correct Answer - Distance between their centres is 25 cm or 5 cm . Let the radii of the circles be `r_(1)` and `r_(2)` `r_(1) = 10cm` and `r_(2) = 15 cm ` By theorem of touching circles, the centres and point of contact are collinear . Here there can be two cases. Case 1`:` The circles touch each other externally Distance between their centres `= r_(1) + r_(2)` `= 10 + 15` `= 25 cm ` Case 2 `:` The circle touch each other internally Distance between their centres `= r_(2) - r_(1)` `= 15- 10 ` `= 5 cm `

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If two circles have radii 10 cm and 15cm and they touch each other. Find the distance between their centres.

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