# Draw tangent circle ?

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Hi all

any can know how draw third circle between two circle if one tangent point know (fixed) (point A) and other tangent in other circle

Edited by issammm

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#### Posted Images

circle, 3point, tan, tan, tan.

Start circle command, pick 3p option, type tan, enter, pick small circle, type tan, enter, pick other circle, type tan, enter, pick line.

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Also C TTR same thing

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Actually I didn't look at the image carefully but now I realize neither solution would work.

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both solution incorrect, if you correct please give me Rx here.

I know tan tan tan but where i pick third tan and how can I determine tangent as point !???

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It all depends on the order of picking the tan points.

I see that I have actually drawn the tangent line to the smaller circle, and that is one of the tan points, as well as the two circles.

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Your circle should have a radius of 9.01545790. Will post later the demonstration.

To draw it create an offset copy to the left circle with above value. Extend the line that join its center with desired tangent point until intersect the new circle; this is the center of the circle you were looking to draw.

Edit: Eldon was faster with his/her graphical solution. Nice one!

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CORRECT, but still can know how you get circle tangents points ??

you look use approximation way not snap point exactly you seek cursor with vertical line and ....

can you try for me replace 5.4152 with 5.3923 ??

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With the new offset, I make the new radius 9.00001399.

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With the new offset, I make the new radius 9.00001399.

you are so closely right but still NOT get the target to answer is 9 try it in your computer and see.

maybe because you use 8 precision I suggest you just using 4 or two enough dear.

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To get a circle of radius 9 exactly, the offset should be 5.39227909

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yes my autocad just 4 precision. can you give me your way in detail you just make vertical line but how you get the second tangent point ?

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Issammm, your original question was not stated correctly. If you had stated that the radius, Rx, was to be 9 and the offset was the variable, you would have been given a solution that was quite easy. Draw the circle with the TTR option, selecting the two circles and specifying 9 for the radius.

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Issammm, your original question was not stated correctly. If you had stated that the radius, Rx, was to be 9 and the offset was the variable, you would have been given a solution that was quite easy. Draw the circle with the TTR option, selecting the two circles and specifying 9 for the radius.

my question is OK, eldon give me correct answers in too accurate.

jst eldon give us more precision than needed.

the Rx = 9 for case 5.3923

regards to all

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Issammm, I gave you above the radius, calculated as per your sketch, with 8 decimals and a solution to use it; isn't that enough for your sketch?

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How can it be when you are changing the value, 5.4152, to a variable and assigning a value where you had a variable, Rx?

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both solution incorrect, if you correct please give me Rx here.

Seems that you were asked for the radius in the first place!

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Seems that you were asked for the radius in the first place!

MSasu you are completely correct.(I hope you explain how you got your answer)

Rob i hope you give me correct answer next time all my replay was clear.

if you want more challenge draw this and find all arcs length.

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It seems that there are not enough figured dimensions. For example, where is G? Is it at the end of a semicircle?

One could guess, but that might not be sufficiently accurate for you

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It seems that there are not enough figured dimensions. For example, where is G? Is it at the end of a semicircle?

One could guess, but that might not be sufficiently accurate for you

points B till I are tangents points except A is a vertex, think well you will get it.

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