3x-y+9=0
If x-2y+4=0 and 2x+y-5=0 are sides of a isosceles triangle having area 10 sq. units.Find the equation of third side?(Note that its an right angled triangle)
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10 Answers
The 2 lines are perpendicular to each other.....so the 2 equal angles will be 45° each.
Now, proceed.....
This question has four answers
pardon, my untidy work, but clearly there are 4 answers
The slopes of the two lines are, -2,1/2
The given lines intersect at (6/5,13/5)
As this is a rt triangle, clearly, we need to find the hypotenuse.......
If the hypotenuse cuts these sides at a distance l, from their intersection, area of the triangle = l2/2 =10
This gives l =2√5
Now, one point on the solution can be found
Here tanθ=1/2
This length turns out to be 4
So, one green line passes through (26/5,23/5)
and the other passes through (-14/5,3/5)
Using point(26/5,23/5), slope 3 in the point slope form of a line,
eqn comes out to be y-3x+11=0
Which is the answer U gave..........
and point(-14/5,3/5), slope 3 gives y-3x-15=0
The other two solutions can be found similarly by finding the length on the other line segment
So, overall it gives 4 solutions, of which only 1 answer appears in the options!!!
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