13, no 14

Logical Reasoning
Try again

From the above diagram, we see that in order to create 1, 2, 3 and 4 unit equilateral triangles on a flat plane, we need 3, 5, 7 and 9 matchsticks respectively.

What is the minimum number of matchsticks on a flat plane needed to create 7 unit equilateral triangles?

No one said that a triangle created by triangles didn't count... i want my point

i see 8 triangles...

Easy Math Editor

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Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$