SOLUTION: Need some help. I'm a parent trying to brush up on my alegbra to help my child. I can only get one of the answers to this problem. Need help with second part. Answers to choose

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Question 695502: Need some help. I'm a parent trying to brush up on my alegbra to help my child. I can only get one of the answers to this problem. Need help with second part. Answers to choose from does not include what I get. Perhaps the correct answer isn't there and the teacher made a mistake...or perhaps it's me. Probgrlme is
A line passes the line (2,-1) and (8,4) a)write an equation for the line in point solpe form. b) rewrite equation in standard form using integers. For point slope I determined slope (y2-y2)/x2-x1 = 5/6. then used y-y1=m(x-x1) to get y+1=5/6 (x-2)..what is the standard form...
Answer by vleith(2983) About Me  (Show Source):
You can put this solution on YOUR website!
see this link on the various forms of equations for lines
http://www.analyzemath.com/line/different_forms.html
The purplemath site is a great resource too.
Part B of this problem asks you to convert the answer you have in part A, into the general form (ax + by = c), where a,b and c are integers. Usually one expects a to be a positive integer.
So let's walk thru the whole thing
%28y%5B2%5D+-+y%5B1%5D%29%2F%28x%5B2%5D+-+x%5B1%5D%29+=+m
%284+-+%28-1%29%29%2F%288-2%29+=+m+
5%2F8+=+m
Use that value for to to solve part a
y+-+%28-1%29+=+%285%2F8%29%28x+-+2%29+
y%2B1+=+%285%2F8%29%28x+-+2%29
I suspect you're answer differs from the one given in the valueof the slope (m). Remember subtracting a negative numbers (minus a minus) ends up as a plus.

Now on to part b
y%2B1+=+%285%2F8%29%28x+-+2%29
8%28y%2B1%29+=+5%28x-2%29
8y+%2B+8+=+5x+-+10
-5x+%2B+8y+=+-18
5x+-8y+=+18