it looks fine.
Remember you can always download this exercise dwg file Here.

alright, i tried to sort it out, and what i get is this:
the distance between upper left circles and lower circle is NOT the same as upper right and lower circle (100 unit). I drew the upper left using “two end points” method by setting D=50 along the line. Here is what I have drawn. Thank you very much your help ^^ https://uploads.disquscdn.com/images/828252f147dd2615c4db93d26639f844f8836a3ff471981a452e485d60a09f1a.png

To get the image above, You do not need to use the tan tan radius command. Just get those lines and the big circle created. Use the information provided in the exercise. Then you have two intersecting points between the lines and the circle to draw the circles as shown the exercises. You will need to use the tan tan radius only once in this exercise, and you can even complete the whole exercise without using it.

Nope. It is just as you see. There is no mistake. U have to figure out a way to adjust them just as they are on the image. This is part of the learning process (This is part of the fun too)

hey guys, am new to using tan tan radius. the image above depicts where i was stuck. need a step further about getting the circles

I see I see. I get it now. I have one more question, is the measurement of the top-left circle r20 and r10 instead of r25 and r15? because my r120 circle will always cross over the r25 circle.

Here you go!

Sorry, When I said start with the 3 circles, I forgot to mention that, the circle of 120 of radius is coming before the two upper circles.

i am having problem on draw the upper curve, i tried using the tan tan radius command (r=120 units, centered at the lower circle’s) but it bends upward. how should i draw it?

Star with getting the 3 circles and place each of them where they should be. (You have all the info to do so, lengths and angles). And the rest is just playing with the LINE and the TAN TAN Radius commands.