srini123 wrote:
Thanks Bunuel, I used similar method for a similar question and I got wrong answer
the question was
what is the area bounded by graph|x/2| + |y/2| = 5?
I got hunderd since
x=10
x=-10
y=10
y=-10
isnt the area 400 ? the answer given was 200, please explain
I think this one is different.
|\frac{x}{2}| + |\frac{y}{2}| = 5After solving you'll get equation of four lines:
y=-10-xy=10+xy=10-xy=x-10These four lines will also make a square, BUT in this case the
diagonal will be 20 so the
Area=\frac{20*20}{2}=200. Or the
Side= \sqrt{200}, area=200.
If you draw these four lines you'll see that the figure (square) which is bounded by them is turned by 90 degrees and has a center at the origin. So the side will not be 20.
Also you made a mistake in solving equation. The red part is not correct. You should have the equations written above.
In our original question when we were solving the equation |x+y| + |x-y| = 4 each time x or y were cancelling out so we get equations of a type
x=some value twice and
y=some value twice. And these equations give the lines which are parallel to the Y or X axis respectively so the figure bounded by them is a "horizontal" square (in your question it's "diagonal" square).
Hope it's clear.
Hii Bunuel.
What is the best approach of finding the points of intersection in order to make the square.
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