Question

I’m having trouble understanding linear equations. I mean, I’ve got half of it, but it’s showing me a table and asking me to find the equation and put it into slope-intercept form. How do I do that?

Answer 1

The slope-intercept form of a linear equation is
`y=mx+c`

You have a table showing x-values and the corresponding y-values. You can think about it as "when x = 0, y = -2 and when x = 1, y = 5..." and so on. What you need to do is find an equation that will tell you the y-value for any x-value you put in to it. Because it says slope-intercept form we know it will look like
`y=mx+c` where m and c are numbers you need to work out.

c is the easiest one to work out, c is the y-value when x = 0. You know from the table that this is -2 hence
`c=-2` so now we just need to work out m and then we have our equation.

We know
`y=mx-2` and we know when x = 1, y = 5 so by putting these numbers into the equation
`5=(m * 1) - 2` so
`m=7`. By putting it all together you get
`y=7x-2` and from this you can work out any y-value by putting in the x-value.