Identity Matrix?! What on the good green Earth is an Identity Matrix?
The short answer is that it’s a square matrix with 1’s down the main diagonal and 0’s everywhere else. For example, a 3×3 identity matrix looks like this:
That’s not particularly useful to understanding what it’s all about though, so let’s have a closer look at it. Continue reading Identity Problems
With all these different types of line equations, how do I actually tell if an equation is a line or not?
This is a really good question. Usually it’s linear relationships (line equations in other words) that are the first type of relationship that you learn about when studying algebra. If you haven’t seen many other types of equations then you probably have very little to compare them to, so it can be difficult to see what it is that makes a line equation a line equation. Continue reading What is a line and what isn’t?
Another one from last year’s Algebra exam: Solve
.
You can find a copy of the exam question paper on the NZQA website here.
Question Three (b): Solve for 
From last year’s Algebra exam: I couldn’t see how to rearrange
to make
the subject.
You can find a copy of the exam question paper on the NZQA website here.
Question Two (c) (i): (abbreviated) Rearrange 
How do I figure out the equation of a line?
There are a number of different forms of line equation. The easiest one to use depends on the information you have about the line.
Let’s, first of all, look at the form of line equation that, generally, people are most familiar with. It looks like this: Continue reading Finding the equation of a line
.
to make 
the subject.