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## #1 Help Me ! » Angles In Circles » 2014-09-15 14:14:59

harrychess
Replies: 1

Triangle ABC is inscribed in the circle and AC = AB. The measure of angle BAC is 42 degrees and segment ED is tangent to the circle at point C. What is the measure of angle ACD? I know the formulas, but I don't know how to get angle ACD. Can someone help me?

## #2 Help Me ! » Midpoints of A Square Proof » 2014-08-04 15:20:01

harrychess
Replies: 3

In square ABCD, E is the midpoint of BC, and F is the midpoint of CD. Let G be the intersection of AE and BF. Prove that DG = AB.

Could someone explain how to prove DG=AB?

## #3 Help Me ! » Medians and Diagonals of A Trapezoid » 2014-07-30 04:53:17

harrychess
Replies: 8

The diagonals of a trapezoid are perpendicular and have lengths 8 and 10. Find the length of the median of the trapezoid.

## #4 Help Me ! » Medians and Altitudes » 2014-07-22 14:28:35

harrychess
Replies: 12

In quadrilateral ABCD, AB=BC=13, CD=DA=24, and angle D=60.  Points X and Y are the midpoints of BC and DA respectively.  Compute XY^2 (the square of the length of X).

## #5 Help Me ! » Special Parts Of A Triangle » 2014-07-17 14:10:37

harrychess
Replies: 1

Angle bisectors TX and UY of triangle TUV meet at point I. Find all possible values of angle V if angle

. As your answer, enter the number of degrees in angle V. If you find more than one possibility, list the possible values in increasing order, separated by commas. What is the answer to this problem and how do you work it?

## #6 Help Me ! » Similar Triangles » 2014-07-10 09:24:53

harrychess
Replies: 1

In a triangle, we have

,
, and
. Find
. What is the answer and how do you get it?

## #7 Help Me ! » Similar TRiangles » 2014-06-23 04:02:53

harrychess
Replies: 23

In triangle ABC, points X and Z are on AB and Y is on AC such that XY is parallel to BC and Zy is parallel to XC. If AZ = 8 and ZX = 4, then what is XB?

## #8 Help Me ! » triangles » 2014-06-19 06:36:17

harrychess
Replies: 4

Let ABC be any triangle. Equilateral triangles BCX, ACY, and BAZ are constructed such that none of these triangles overlaps triangle ABC.

a) Draw a triangle ABC and then sketch the remainder of the figure. It will help if  ABC is not isosceles (or equilateral).

b) Show that, regardless of choice of  ABC, we always have AX = BY = CZ.

Problem A I can manage(obviously), but I dont know how to do B. If I made ABC an equilateral triangle, it would be easy, so I dont want to do that. Could you explain how to prove if ABC was obtuse scalene?

## #9 Re: Help Me ! » Algebra II Type Problems » 2014-06-13 08:59:05

yes, all the way to 1 over the square root of 9998 plus the square root of 10000.

## #10 Re: Help Me ! » Algebra II Type Problems » 2014-06-13 08:40:19

On the first problem, it goes like this. One over the square root of 100 plus the square root of 102. That is added to one over the square root of 102 plus the square root of 104. This continues all the way to one over the square root of 9998 plus the square root of 10000.

## #11 Help Me ! » Algebra II Type Problems » 2014-06-13 08:13:40

harrychess
Replies: 25

Could someone explain how to do these problems?

Compute the sum

Sorry, I can't figure out how to put this problem without code.

Find the ordered quintuplet (a,b,c,d,e) that satisfies the system of equations
a+2b+3c+4d+5e=177
2a+3b+4c+5d+e=154
3a+4b+5c+d+2e=146dss
4a+5b+c+2d+3e=138
5a+b+2c+3d+4e=165

The sequence

, has the property that
for all
, then determine
.

Find the largest four-digit value of t such that

}...
} is an integer.

## #12 Help Me ! » Geometry Problem » 2014-06-12 05:13:56

harrychess
Replies: 3

Point X is on side

of
such that
, and
. Find
in degrees.

## #13 Help Me ! » Sequences » 2014-06-05 14:06:32

harrychess
Replies: 28

Let

Find the largest n so that

Compute the sum

## #14 Re: Help Me ! » Geometric Sequences » 2014-05-29 13:48:12

I got 2 solutions Bob. (18,5) and (9,8). Yes, a and n have to be positive integers.

## #15 Re: Help Me ! » Geometric Sequences » 2014-05-29 11:57:53

Penn writes a 2013-term arithmetic sequence of positive integers, and Teller writes a different 2013-term arithmetic sequence of integers. Teller's first term is the negative of Penn's first term. Each then finds the sum of the terms in his sequence. If their sums are equal, then what is the smallest possible value of the first term in Penn's sequence?

## #16 Re: Help Me ! » Geometric Sequences » 2014-05-28 14:27:53

Part (a): Find the sum

in terms of a and n.

Part (b): Find all pairs of positive integers

such that
and

I know how to do part a ,but I don't know how to do part b. Could someone explain it to me?

## #17 Help Me ! » Geometric Sequences » 2014-05-26 14:04:52

harrychess
Replies: 12

The

term in a certain geometric sequence is
and the
term in the sequence is
. What is the
term?

## #18 Re: Help Me ! » Floor and Ceiling » 2014-05-23 11:10:29

How are you supposed work do the other two problems?

## #19 Re: Help Me ! » Floor and Ceiling » 2014-05-21 14:10:25

bobbym wrote:

Hi Dylan;

Let f(x) = floor of \frac{2-3x}{x+5}. Find f(1)+f(2)+f(3)...+f(999)+(1000).

Sorry, I gave you the problem with a typo. It should be f(1000).

## #20 Re: Help Me ! » Floor and Ceiling » 2014-05-21 14:05:01

So... how are you supposed to work these type of problems?

## #21 Re: Help Me ! » Floor and Ceiling » 2014-05-21 14:04:01

found that out... ok

So it would be

?

## #23 Re: Help Me ! » Special Functions » 2014-05-16 13:03:24

Wait, isnt it root 5?

## #24 Re: Help Me ! » Special Functions » 2014-05-16 12:39:17

dont you set if its positive or its negative? 2 cases?

## #25 Re: Help Me ! » Special Functions » 2014-05-16 12:29:15

how did you do it?