lines
posted by Amanda on .
The line through (2,3) and parallel to 2x+5y=3.
The line through (2,3) and perpendicular to 2x+5y=3.
I just can't remember how to solve either of these kinds of problems and i can't find my notes on the subject.

The slope "m" of the first line must be 2/5. You get that by rewriting
2x + 5y = 3 as
y = (2/5)x + 3/5
The slope "m" of the second line must be 5/2, because the product of the slopes of the two lines must be 1.
When you know the slope m and the point x1, y1 that the line goes through, the equation of the line can be written
(y  y1)/(x  x1) = m