Answer:
You don't really need to do it, but it helps you keep things more organized and easier to follow. Imagine if you're doing some multi-variable equation,
2a + 5b + 4d + 3c + b + a + 2d
that looks like a mess, it'll be easier to look at if you put all the similar variables next to each others like this:
a + 2a + b + 5b + 3c + 2d + 4d
(a + 2a) + (b + 5b) + 3c + (2d + 4d)
now you can add them up much easier.
First step: you have to plug in 6y+3 into the equation and solve
Example: 6y+3+2y = 5
<h3>
Answer: -6/5</h3>
Explanation:
The blue diagonal line goes through the two points (0,2) and (5,-4). These are shown as the dark blue enlarged points. You can pick any other points you want that are on the diagonal line, though these are the easiest as they stand out the most.
Use the slope formula to find the slope through these points
m = (y2-y1)/(x2-x1)
m = (-4-2)/(5-0)
m = (-6)/(5)
m = -6/5
The negative slope means the line goes downhill as you move from left to right along the diagonal line.