Some teachers will take your paper, tear it up, and throw it in the trash if it is done in pen! Wow! I know that sounds harsh but you should only have to do your math in pen once to realize that pencil and eraser are the way to go. I'm not sure why students like using pen. Perhaps pens glide more easily across the page, or create darker print, or maybe it just feels like a more grown up thing to do. In any case mistakes in math are inevitable and being able to correct the small typos or even to start a problem completely over is the purpose of pencils. What I recommend is using a pencil and eraser that are easy and enjoyable to use. Some mechanical pencils have lead that is so fragile that the lead constantly breaks. Some erasers are so hard(usually the pink ones) that instead of erasing they just make a mess of things. So get some decent writing(and erasing) utensils that will make doing your math more enjoyable and save the pen for brainstorming your big ideas on the back of envelopes and napkins!
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