How to Subtract
Question
One of the first places to subtract is using
Hi, my name is Bassem Saad. I'm an associate math instructor and a Ph.D. candidate, and I'm here today for About.com to show you how to subtract.
Instructions for How to Subtract

One of the first places to subtract is using a number line. You can make your own number line by first drawing a line and 16 marks. Then you want to label each mark by counting, starting from zero, one, two, three, all the way to 15. Now we're ready to subtract seven, minus one. The first thing you want to do is find seven on your number line. We're subtracting one, so that means we want to go back one step. Well, one before seven is six, so your answer is six. Seven, minus one, equals six.
Other Ways to Learn How to Subtract

We can also learn how to subtract using cut-outs. With cut-outs, we start with a number of fun shapes, like stars. Since our problem begins with a seven, we want to count out seven stars – one, two, three, four, five, six, seven. Then we want to minus one star – minus means take away. So we want to take away one star. Then we count how many we have left – one, two, three, four, five, six. So we have six stars left. That means seven, minus one, equals six. So let's take a look at a few more examples. How about eight, minus five? We want to use the same method.
More Tips for Learning How to Subtract

Find eight on the number line, and this time we want to count back five, so – one, two, three, four, five. Well, that takes us to three. So eight, minus five, equals three. We can do the same thing using the cut-out method. Again, we start with eight. So we count eight stars – one, two, three, four, five, six, seven, eight. Well that's minus five – that means we want to take away five. So we look for five – one, two, three, four, five. This is five, and we just take them away. What we have left is three – one, two, three stars. So now we know how to subtract.