This is another video in the Year 9 series relating to Linear Relations. This video looks at what the gradient-intercept form is and how we can write equations of straight lines using it. Otherwise known as y=mx+c, or in other year levels y=a+bx, I take a look at what we need to be able to write the equation of a straight line. If we are given a gradient and a point on the line, we can use some pretty simple Mathematics to find the equation of the straight line. This video has a number of worked examples and the theory is explained in an easy to understand way.