I know the formulas for coordinate geometry of the straight line and I've done a fair bit of it but I have trouble when it comes to converting equations into lines with coordinates.(adsbygoogle = window.adsbygoogle || []).push({});

Heres an example of a question I can't answer

L is the line 2x - 3y - 7 = 0. Verify that the point a(-1,-3) is in L.

Find

i) the slope of L

ii) the coordinates of the points where L intercepts the y-axis

iii) the equation of the line parallel to L through the point (-3,0)

First off I assume that to verify (-1,-3) is on the line L I just plug those values into the equation for L. I did that and the answer comes out to 7 not 0 so I assume (-1,-3) is not on the line.

i) To find the slope I would use the formula-a/bwhich would give me -2/3. Another way I'd get the slope is to rearrange the equation into y = m(x) form and doing that I get the same result -2/3. Is this correct?

ii) To find the y intercept of a point I would arrange the equation into its slope intercept form and heres what I gety = -2/3(x) + 7so in this case I'd assume the y intercept is 7 but this seems to be incorrect

iii) for this one I'd use the formulay - y1 = m(x - x1)

So the main part of this I'm having trouble with is finding the y intercept of line L because if I try to get it by letting y in the equation = 0 I get a different answer to 7.

I also don't get why they say "verify" that points on the line if it isn't even on the line. I woulda thought they'd say "find out if point (-1,-3) is on L"

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# Couple of questions on linear geometry

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