#grade07

Most of us have been taught (or indoctrinated, to be honest) to accept that a negative number multiplied by a negative number yields a positive number, but would be hard-pressed to explain why. Even adults

I have introduced Mr Sandman and Mr Upside-Down in an earlier article. In this article, I shall illustrate integer arithmetic with more examples. Remember that what our Sandman calls a “hole” is a “mound”

What is - (a – b)? Do you have a quick way to simplify this? It turns out that the answer is very easy! Just swap the two quantities. For example, -( 3 - 5 ) = 2. This is the same as result of 5 – 3. How

In linguistics, double negatives are a no-no. Two wrongs do not make a right. Or do they? Well, if you ask a mathematics teacher, this might be the case. For example, -(-2) = 2. But why? Why? Why? Tell

This article introduces what I call the "crossing the bridge" short-cut. Here is an example of an algebraic equation solved using the standard orthodox methods. To "get rid" of the

I have written about Flipping and the Escalator Trick. It is possible to combine the two. Here is an example done previously by the escalator only, but now re-done using a combination of Flipping and

Here is a problem done by standard orthodox methods. We multiply both sides of tbe equation by 3x, which is a legit procedure. On the LHS, we cancel the x's, and on the RHS, we cancel the 3s. We now have

I introduced The Escalator Trick, a very powerful short-cut in Part 1 and Part 2 Today, I show you how to melt a "difficult" problem like wax. Take a look at this. How do you even begin? You

Yesterday, I gave some easy examples on "the escalator trick" Part 1 which is a useful short-cut. Today we tackle some slightly more challenging examples. What if the unknown ('x') appears in

In this article, I introduce an algebraic short-cut. This is for Secondary 1 mathematics in Singapore, approximately grade 7. Let us look at an example. The standard way is to multiply the left-hand side