Triangle ABC. Mark the incenter I, where the angle bisectors meet, draw the segments AI, BI and CI, and draw the circle centred at I that touches all three sides. Check that the circle is tangent to AB, BC and CA.
Forma Visuals · Draw a geometry figure · Examples
Incircle construction
The point where the angle bisectors meet and the circle that touches all three sides, for a worksheet or an exam.
For educators · TikZ
01 The figure
Drawn from the code that came back.
valid · vector-graphics@0bd7c5a4 · 1 credit · 2026-10-07
The check covers the properties the figure states, in the figure you receive. Measurements are not compared with the drawing: read the source.
02 The request
In plain words.
03 What came back
A tikzpicture.
\begin{tikzpicture}[x=1pt,y=1pt]
\path[use as bounding box] (0,0) rectangle (297.41,213.16);
\draw[draw=black!45,line width=0.4pt,dashed] (18.33,19.33) -- (278.33,19.33);
\draw[draw=black!45,line width=0.4pt,dashed] (278.33,19.33) -- (105,192.66);
\draw[draw=black!45,line width=0.4pt,dashed] (105,192.66) -- (18.33,19.33);
\draw[draw=black,line width=0.6pt] (18.33,19.33) -- (122.66,83.81);
\draw[draw=black,line width=0.6pt] (278.33,19.33) -- (122.66,83.81);
\draw[draw=black,line width=0.6pt] (105,192.66) -- (122.66,83.81);
\draw[draw=red!75!black,line width=1.1pt,fill=none] (122.66,83.81) circle[radius=64.48pt];
\filldraw[draw=none,line width=0.4pt,fill=black] (18.33,19.33) circle[radius=1.3pt];
\filldraw[draw=none,line width=0.4pt,fill=black] (278.33,19.33) circle[radius=1.3pt];
\filldraw[draw=none,line width=0.4pt,fill=black] (105,192.66) circle[radius=1.3pt];
\filldraw[draw=none,line width=0.4pt,fill=black] (122.66,83.81) circle[radius=1.3pt];
\node[text=black,anchor=center,font=\fontsize{10pt}{12pt}\selectfont] at (11.75,12.25) {$A$};
\node[text=black,anchor=center,font=\fontsize{10pt}{12pt}\selectfont] at (285.87,19.33) {$B$};
\node[text=black,anchor=center,font=\fontsize{10pt}{12pt}\selectfont] at (105,200.91) {$C$};
\node[text=black,anchor=center,font=\fontsize{10pt}{12pt}\selectfont] at (122.66,75.56) {$I$};
\node[text=black,anchor=center,font=\fontsize{10pt}{12pt}\selectfont] at (186.65,136.48) {incircle};
\end{tikzpicture}
04 When to use it
Where this figure helps.
- Teaching the incentre and the inscribed circle.
- State what must hold, as the request does; only properties the figure states are checked.
- Measurements you write are not compared with the drawing; describe the construction instead.