equation standards?!? (1 Viewer)

[Teh Duke]

hey guys,

I know this may sound like a stupid question but are there any rules for how to write equations in your answers. For example in questions that ask for the equation of a line i always write my answer in the form y=mx+b, but in the solutions they seem to have the habit of bringing everything to one side and equating it to 0. Same thing with equations of circles, i leave my answer in the form (x-h)^2 +(y-k)^2 = r^2 but in the answers they bring it all to one side.

So my question is, are there any rules for this, and can i lose marks for not leaving my answers in the correct form.

I'd hate to lose marks for something stupid like this.

 

[eskimoh]

yeh id like to kno whether theyll take marks off for that too.. cos i tend to do that haha

 

[Teh Duke]

i dont understand why they do that, i leave the equations in a useful form, so you can just read information off it, like the gradient and y-int for a line.
with the way they leave it you have to re-simplify it just so you can get the same information.

 

[dolbinau]

I think general form of mx+b will be both accepted. If they specifically ask for gradient intercept form or the likes then you'd have to do that.

I once left an equation in neither general nor intercept form (Basically half terms on each side) and got it wrong, which I shouldn't have. But meh.

 

[Trebla]

hey guys,

I know this may sound like a stupid question but are there any rules for how to write equations in your answers. For example in questions that ask for the equation of a line i always write my answer in the form y=mx+b, but in the solutions they seem to have the habit of bringing everything to one side and equating it to 0. Same thing with equations of circles, i leave my answer in the form (x-h)^2 +(y-k)^2 = r^2 but in the answers they bring it all to one side.

So my question is, are there any rules for this, and can i lose marks for not leaving my answers in the correct form.

I'd hate to lose marks for something stupid like this.

Unless otherwise specified, you can leave your equations in any form you like as long as it is correct and simplified.
So for example if you were asked to find the equation of the tangent to the parabola y = x² at (1,1), you can leave your answer as y - 1 = 2(x - 1), unless the question says "in simplified form" or something like that.
If you are asked to prove an equation, then of course you have to simplify and rearrange it in the form specified in the question.