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by DanaJ » Sun Apr 19, 2009 4:22 am
First off, it's important to know that if lines k and m are parallel, then they have the same slope.

Now, let's look at the stmts:

The slope of a line will be m in the equation: y = mx + n (also known as the equation of a line). In order to determine if a slope is negative, you need at least two points on the line: A(x1, y1) and B(x2, y2).
You'd get the slope m by solving the system:
y1 = m*x1 + n
y2 = m*x2 + n
Since we're only given one point at a time in each stmt, they're clearly not enough by themselves.

Put the two stmts together and you still don't get much: you still have only one point for each line. This is why I'm sticking to the OA.
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by 4seasoncentre » Sun Apr 19, 2009 7:07 am
I would draw a quick axis and roughly plot the points (3,2) and (-3,2)

with statement 1, it is fairly obvious that the slope can be whatever it wants.
with statement 2, I imagining two parallel lines and I'm mentally imagining them moving around. I can see them both with positive slopes, then I shift and I can see them running with negative slopes.

Answer is E.
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by 4seasoncentre » Sun Apr 19, 2009 7:18 am
I would draw a quick axis and roughly plot the points (3,2) and (-3,2)

with statement 1, it is fairly obvious that the slope can be whatever it wants.
with statement 2, I imagining two parallel lines and I'm mentally imagining them moving around. I can see them both with positive slopes, then I shift and I can see them running with negative slopes.

Answer is E.
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Master | Next Rank: 500 Posts
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by 4seasoncentre » Sun Apr 19, 2009 7:34 am
I would draw a quick axis and roughly plot the points (3,2) and (-3,2)

with statement 1, it is fairly obvious that the slope can be whatever it wants.
with statement 2, I imagining two parallel lines and I'm mentally imagining them moving around. I can see them both with positive slopes, then I shift and I can see them running with negative slopes.

Answer is E.
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