yellowho wrote:I was thinking of combining originally by saw 3 variables and 2 equation and stopped.
The "rules" of algebras like "more unknown than equations can't be solved" etc are applicable only when there is n other information is available. When we have other data, why don't we try to use them rather than blindly following the rules?
yellowho wrote:Algebraically, its not that helpful. It's only helpful if you know that j cannot be the same as the slope in the original line. How did you solve it? Did you say (3+2j)x=0 X= 0 or 3+2j=0 thus J=-3/2 since j cannot be -3/2 then x must be zero. Or did you some how know based on some property.
If you take j = -3/2, then the equation of two lines will be same and they will coincide on each other, i.e. the two lines will intersect at infinite number of points. Thus from statement 1 we conclude either the lines intersect at point (0, 7) or at infinite number of points which includes point (0, 7) too. Hence in any case they are intersecting at point (0, 7).
Here is another approach you may find useful:
- The Equation for line B is jx - y = -7
Rearranging, y = jx + 7
Thus, only the slope of the line B depends on j.
But we know the y-intercept of line B, which is equal to 7.
Hence B always passes through (0, 7) and we conclude it from the question stem itself.
Now statement 1 is clearly sufficient.
