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#1 Re: Help Me ! » Help on Algebra Problem » 2014-09-08 13:01:33
Yes, you were (as always)! 
#2 Re: Help Me ! » Help on Algebra Problem » 2014-09-08 10:21:15
Thanks for replying bobbym! I might have more questions that I may post here and would appreciate it if you helped me answer them.
Thanks again!
#3 Help Me ! » Help on Algebra Problem » 2014-09-07 15:07:08
- math137
- Replies: 5
This is the problem:
If (x - a)(x - 1) + 1 = (x + b)(x + c) is true for all x and if a, b, and c are integers, find the sum of all possible values of a.
Thanks!
#4 Help Me ! » Geometric Proof » 2014-08-10 09:27:41
- math137
- Replies: 3
Hello,
How would you prove this:
Two circles are externally tangent at point P, as shown. Segment CPD is parallel to common external tangent AB. Prove that the distance between the midpoints of AB and CD is AB/2.
Thanks.
#5 Re: Help Me ! » Circle Geo Problems » 2014-08-08 12:31:14
I actually got the first 2 problems. Thx EVW on your help on problem 2! 
I still need help on this problem though: Equilateral triangle ABC has centroid G. Triangle A'B'C' is the image of triangle ABC upon a dilation with center G and scale factor -2/3. Let K be the area of the region that is within both triangles. Find K/[ABC]. I thought K was the area of the dilated equilateral triangle but that doesn't seem to be the case (the answer I got was 4/9).
Thanks!
#6 Re: Help Me ! » Circle Geo Problems » 2014-08-08 12:22:32
I think it's supposed to. The heptagon is the white figure and then the set of points that are within a distance of 1 from some point on or inside the heptagon is the shaded part.
#7 Re: Help Me ! » Circle Geo Problems » 2014-08-08 09:19:58
Could someone plz help? I really need help because it's due soon.
#8 Re: Help Me ! » Circle Geo Problems » 2014-08-08 06:20:59
I have one more problem I need help with. This isn't really circle geo but...
3. Equilateral triangle ABC has centroid G. Triangle A'B'C' is the image of triangle ABC upon a dilation with center G and scale factor -2/3. Let K be the area of the region that is within both triangles. Find K/[ABC].
#9 Help Me ! » Circle Geo Problems » 2014-08-08 06:19:27
- math137
- Replies: 19
Here's a few problems I need help with:
1.We are given a regular heptagon of side length 1. Let S be the set of points that are within a distance of 1 from some point on or inside the heptagon, but not including the heptagon itself. Find the area of S.
2. Let C and D be points on the semicircle with diameter \overline{AB}. If AD = BC = 3 and CD = 7, then find the radius of the semicircle. 
Thx!
#10 Re: Help Me ! » Geo Problems » 2014-08-08 06:14:26
Ok thx guys!
#11 Re: Help Me ! » Geo Problems » 2014-08-08 04:41:50
I have made the three inequalities involving the three side lengths. From that, I get n>-7, n>3/2, n>3, so from this I conclude n>3. From the angle inequality you gave me, I got n<13 so shouldn't there be 17 different possible values? It says it's wrong though.
#12 Help Me ! » Geo Problems » 2014-08-07 14:12:21
- math137
- Replies: 13
Here's a couple problems that I'm stuck on. It would be appreciated if someone could help.
1. One side of a triangle is 10. What is the smallest possible perimeter of the triangle, if it is known to be a positive integer?
2. A (non-degenerate) triangle with integer sides has perimeter 12. How many such non-congruent triangles are there?
3. Two sides of an acute triangle are 8 and 15. How many possible lengths are there for the third side, if it is a positive integer?
4. The distance from Capital City to Little Village is 660 miles. From Capital City to Mytown is 310 miles, from Mytown to Yourtown is 200 miles, and from Yourtown to Little Village is 150 miles. How far is it from Mytown to Little Village?
5. In the triangle shown, n is a positive integer, and angle A>angle B>angle C. How many possible values of n are there?
Thx!
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