Math Series #1 – Negative Numbers

Math section talking about negative numbers.

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One of the series I plan to start with this blog are a series of tutoring sections. The goal of this is to give some help where I have quite a bit of knowledge. I want to be able to help people who don’t believe they get to use math see that there are many points in our everyday life that having a strong math understand is beneficial.

I chose this subject because I wanted to start somewhere that might be giving people problems, it is simple enough to write a brief explanation for, easy homework, and fairly straight forward to move up after this. So if you like it, please leave me a comment and/or follow me for more. With everything I end up doing here the continuation of something or the discontinuation of something is completely dependent on you.

 

Negative Numbers

We all know about positive numbers. We use them almost every day: adding our money, counting bananas, and many more. We actually use negative numbers more often then we believe. Whenever you make a transaction on your credit card, visa, or check you are using negative numbers. We see these equations simplified most of the time as $10 – $4 = $6. This isn’t wrong but there is more to this equation then meets the eye. Most people can agree the addition equations are the easiest. 10 + 5, 1999 + 1, 54323 + 1231234, and so on. It is easier to count to a higher number. All the way from school we learn to count forwards and backwards.

The equation 10 – 4 can be changed to 10 + (-4). This will give you the same answer. In pre-algebra classes this is about the time they will teach you the number line. A number line is a series of numbers shown on a picture that is a line. Something sort of like this:

 

<(-10)–(-9)–(-8)–(-7)–(-6)–(-5)–(-4)–(-3)–(-2)–(-1)–0–1–2–3–4–5–6–7–8–9–10>

Yours may be a bit more elegant but they serve the same purpose. They allow people to visualize the equation. If you have something like 10-4 you can find the answer by starting at the number 10 on the number line and counting backwards 4 numbers. This will bring you to the number 6. If you get something that looks like -4 + 10 you get to move right instead of left. Starting at -4 you will count right 10 spaces bringing you to 6.

While most of our computations are a bit more complicated then this it is still the basic way we solve these problems. Whether you use the number line or you are confident enough to do it in your head both ways will suffice to do the problems.

Each section I will give some homework that you can try. I will answer these problems in my next mathematics post. I will give some normal equations as well as word problems. I will always try to give you something that you can answer that helps show the relation and how we use it in real life.

Homework

1.  25 – 13

2.  20 + (-4)

3.   -147 + (-253)

4.   5 + 13 – 7 + (-24) – (+37)

5.   You find twenty dollars in your couch. You decide that you are going to test your luck at the casino. You take the twenty dollars and put it into the slot machine. After a couple spins you are down to seven dollars. Five spins after that you hit a mini jackpot and have a total of one hundred dollars. You test your luck and play some more spins. You get brought down to thirty-eight dollars. You decide you will play it down to twenty dollars. Before you reach twenty dollars (at twenty-three dollars) you hit a win of twenty-seven dollars. What is your total and how much did you spend to get this total?

 

 

The next subject will be on multiplication and division. We will talk about the beginnings of Algebra and we will start introducing the PEMDAS concept.

 

Thanks for reading and study hard!

-Gregg