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**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?

**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?

**harrychess**- Replies: 8

Please Help! I need someone to explain how to work this problem.

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

**harrychess**- Replies: 12

Help please! An answer and explanation will do.

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).

**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?**harrychess**- Replies: 1

In a triangle, we have

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

**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?

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

**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.**harrychess**- Replies: 3

Point X is on side

of such that , and . Find in degrees.**harrychess**- Replies: 28

Let

Find the largest n so thatCompute the sum

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

Part (a): Find the sum

in terms of a and n.Part (b): Find all pairs of positive integers

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

**harrychess**- Replies: 12

The

term in a certain geometric sequence is and the term in the sequence is . What is the term?How are you supposed work do the other two problems?

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).

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

found that out... ok

So it would be

?Wait, isnt it root 5?

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

how did you do it?