The answer is 20. You use 20 markers for it all.
Okay so make a coordinate plane, insert the numbers in the right place, then count what’s in between, you got this, I’ll totally help you if you didn’t get it.
This is true. The sum of interior angles always add up to 180<span>°.
Hopefully this helps! If you have any more questions or don't understand, feel free to DM me, and I'll get back to you ASAP! :)
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