# Faq/Draw/105

< Faq‎ | Draw

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## How do I draw a regular equilateral triangle?

The Drawing toolbar has a button to draw an isosceles triangle but not an equilateral triangle. To draw one, you must do a little geometry. In fact, an equilateral triangle is an isosceles triangle whose height h is:

$h=\mathit{a.}\sin \left(\frac{\Pi }{3}\right)=\mathit{a.}\sin \left(60\circ \right)=\mathit{a.}\frac{\sqrt{3}}{2}\approx a\times \mathrm{0.866}$ with a representing the length of any edge of the triangle.

To draw an equilateral triangle:

• click on the triangle to the right of the Basic Shapes icon to open the Basic Shapes toolbar. In the toolbar, click on the Isosceles Triangle button.
• click and drag to draw a triangle of about the size desired;
• select the Format ▸ Position and sizemenu;
• make sure Keep ratio is unchecked;
• the height so that it equals the width multiplied by 0.866,
• the width so that it equals the height divided by 0.866,or
• both, maintaining the proportion 0.866 between the height and the width;
• If you change the size of the triangle, click Keep ratio to keep the length of the three sides equal.
• Click OK.

Another way to create equilateral triangle is to:

• Draw a line, holding ⇧ Shift, so it is a straight line.
• Click on it, press F4 to open properties.
• Position and size, set size to 100mm.
• Click on ok
• Use copy and paste to create a copy.
• Click on it, press F4 to open properties.
• Rotation, select bottom left for the rotation point, and 60".
• Create another copy of the base line, click on it, press F4
• Rotation, select bottom right for the rotation and 300".
• Select all lines, and choose 'modify/combine' from the menu.