basically i did the edexcel may 2012 c1 exam,and i had a doubt on question 9 [part b] , where it asked to find the perpendiculal line l1, I did not convert it to y=mx+c at the beginning meaning i got the wrong perp gradient and therefore the wrong answer.my question is that will i get marks for showing the right proceedure but using the wrong numbers.
if so how many marks will i get?
and will there be any error carried forward marks for part c ?
the may 2012 c1 paper is below.
Is this right?