Straight line problem: line through (-5,-4) meets x+3y+2=0, 2x+y+4=0, x-y-5=0 at B,C,D respectively. If (15/AB)^2+(10/AC)^2=(6/AD)^2, find line's eqn.
- Thread starter arjunn
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What are your thoughts? What have you tried? How far have you gotten? What recent results/rules/theorems have been covered in class? ("Read Before Posting")
Please be complete. Thank you!
lev888
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Let's consider an easier problem. A line through point A(1, 2) intersects the line y=2x+3 at point P. Distance AP is given. Find the equation of the first line. How would you approach this problem?
Does AB in [(15/AB)2] imply length of the line AB?
You have to find a relation with 15
Here we can easily find the coordinates of the point where it intersects
x-1/cos theta= y-2/sin theta = distance AP
Is the distance perpendicular or minimum/maximum?
lev888
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What theta? Don't see any angles in the question.
The distance is from point A to point P.
We can imagine a horizontal line with angle theta
lev888
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Sure, you can make whatever additional constructions you want and you can introduce whatever variables you want. But then you should post the diagram showing the constructions and your solution must include steps where all of your variables are expressed through values actually given in the problem.
What? Bro we need to find the angle can you not see easily or understand in the giving first equation that we have values Of x and distance so in the formula qe only need to find the angle so with help of giving information we found the angle and solved