GMATPREP - PS problem -3
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Vishal please check the attachment.I have tried to explain but dont know how much i am correct.
Hope it helps you.
Hope it helps you.
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Thanks and regards,
Saurabh Mahajan
I can understand you not winning,but i will not forgive you for not trying.
Saurabh Mahajan
I can understand you not winning,but i will not forgive you for not trying.
- Tani
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You can see this most easily by simply drawing the circle and then the lines that would fit the clues given.
1. The equation of the unit circle described is x^2 + y^2 = 1 - draw this.
Clue a.
2. Draw a line that crosses the x axis at 1/2. No matter what slope, it must intercept the circle.
3. Draw a line that crosses the x axis at 20 and is perpendicular to the x axis. It will never intercept the circle.
Clue B.
4. Looking at the same two drawings above, if the x-intercept is 1/2 you intersect the circle no matter what the slope so you can have a slope of - 1/10 and intersect the circle.
5. Looking at the second drawing, with an x intercept of 20, your equation becomes 0 = (-1/10)*(20) + b.
the y intercept is then +2 and the line passes above the circle.
Looking at the two together, as in steps 4 and 5 you still get both a yes and a no. The information is insufficient.
1. The equation of the unit circle described is x^2 + y^2 = 1 - draw this.
Clue a.
2. Draw a line that crosses the x axis at 1/2. No matter what slope, it must intercept the circle.
3. Draw a line that crosses the x axis at 20 and is perpendicular to the x axis. It will never intercept the circle.
Clue B.
4. Looking at the same two drawings above, if the x-intercept is 1/2 you intersect the circle no matter what the slope so you can have a slope of - 1/10 and intersect the circle.
5. Looking at the second drawing, with an x intercept of 20, your equation becomes 0 = (-1/10)*(20) + b.
the y intercept is then +2 and the line passes above the circle.
Looking at the two together, as in steps 4 and 5 you still get both a yes and a no. The information is insufficient.
Tani Wolff
- Tani
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Clue b is simply the slope of hte line. Draw a line with a -1/10 slope and then draw several lines parallel to it. You will see that some of them will intersect your circle and some will not.
Tani Wolff