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#1 Re: Help Me ! » HELP please!!!!! » 2016-09-11 05:03:01

My class code is JB47 and i need help with everything from 2 to verify #4. Could you tell me the equations and i'll go check if it works and maybe alter it a bit if needed.

#2 Re: Help Me ! » HELP please!!!!! » 2016-09-10 16:42:57

Here's the first 3 problems:
http://imgur.com/a/A2bJ8

i need an equation for each one so that it catches the stars. Thank you!!!

#3 Help Me ! » HELP please!!!!! » 2016-09-10 03:18:33

apsara123
Replies: 7

My teacher assigned this homework called marble slide parabolas and I need to make it up to slide 16 but it's way too hard and I'm dying trying to figure it out.
Here's the link :
https://teacher.desmos.com/marbleslides-parabolas

Go there create a class code and try the problems...it's really hard. Can someone please give me the equation for all the slides from 4-16. THANK YOU so much!!!

#4 Re: Help Me ! » Triangles » 2016-08-23 04:12:55

How do you get that for K in your coordinate geometry solution?

#5 Help Me ! » Help With Problem » 2016-08-15 02:58:27

apsara123
Replies: 4

I need help with these 2 problems:

1)Two circles are externally tangent at point $P$, as shown. Segment $\overline{CPD}$ is parallel to common external tangent $\overline{AB}$. Prove that the distance between the midpoints of $\overline{AB}$ and $\overline{CD}$ is $AB/2$.

3c1BBlj.png

2)In triangle $ABC$, $AB = AC$, $D$ is the midpoint of $\overline{BC}$, $E$ is the foot of the perpendicular from $D$ to $\overline{AC}$, and $F$ is the midpoint of $\overline{DE}$. Prove that $\overline{AF}$ is perpendicular to $\overline{BE}$.

Can you solve these 2 problems by writing simple geometry proofs? THANK YOU!!

#6 Help Me ! » Help With Problem » 2016-07-28 06:33:49

apsara123
Replies: 4

I need help with these problems...can you give detailed solution. Thank you!

1)In right triangle $MNO$, $\tan{M}=\frac{5}{4}$, $OM=8$, and $\angle O = 90^\circ$. Find $MN$. Express your answer in simplest radical form.

2)Points $A$ and $B$ are selected on the graph of $y = -\frac{1}{2}x^2$ so that triangle $ABO$ is equilateral. Find the length of one side of triangle $ABO$.

IMAGE:http://imgur.com/a/gLRIK

3)Find $\cos (-135^\circ)$.

#8 Re: Help Me ! » Problems » 2016-07-08 09:47:56

I still need help with part a and part b. I used congruent triangles to show that the lengths are equal in part a but I can't prove their perpendicular. And for part B I have absolutely no idea to start! Please help. thank you.

#9 Help Me ! » Problems » 2016-07-05 09:46:00

apsara123
Replies: 6

I need help with these problems:

1)Let $\triangle ABC$ be a right triangle such that $B$ is a right angle. A circle with diameter of $BC$ meets side $AC$ at $D.$ If the area of $\triangle ABC$ is $150$ and $AC = 25,$ then what is $BD$?

2)A decorative arrangement of floor tiles forms concentric circles, as shown in the figure to the right. The smallest circle has a radius of 2 feet, and each successive circle has a radius 2 feet longer. All the lines shown intersect at the center and form 12 congruent central angles. What is the area of the shaded region? Express your answer in terms of $\pi$.

Picture for number 2 is :icYkZie.png

3) Let $ABC$ be a triangle. We construct squares $ABST$ and $ACUV$ with centers $O_1$ and $O_2$, respectively, as shown. Let $M$ be the midpoint of $\overline{BC}$.
iYgZQzw.png


(a) Prove that $\overline{BV}$ and $\overline{CT}$ are equal in length and perpendicular.

(b) Prove that $\overline{O_1 M}$ and $\overline{O_2 M}$ are equal in length and perpendicular.


Thank you so much!!

#10 Re: Help Me ! » Help » 2016-06-24 09:00:48

Here's the link:
http://imgur.com/lqJfg3W

#11 Re: Help Me ! » Help » 2016-06-23 05:45:13

How do I post a picture?

#12 Re: Help Me ! » Very Difficult Angle Bisector Problems » 2016-06-22 10:46:29

1)From $\triangle TIU$, we have $\angle ITU + \angle IUT + 109^\circ = 180^\circ$, so
\[\angle ITU  + \angle IUT = 71^\circ.\]
Since $\overline{TX}$ and $\overline{UY}$ are angle bisectors, we have $\angle ITU = \frac{\angle VTU}{2}$ and $\angle IUT = \frac{\angle VUT}{2}$. So, we have
\[\frac{\angle VTU}{2} + \frac{\angle VUT}{2} = 71^\circ,\]
which gives us $\angle VTU + \angle VUT = 142^\circ$. Finally, from $\triangle VTU$, we have
\[\angle V = 180^\circ - \angle VTU - \angle VUT = \boxed{38^\circ}.\]

2)From the Angle Bisector Theorem, we have $BC/BF = AC /AF$. Since $AF = AB - BF = 8-BF$, $AC = AE +CE = 10$, and $BC = 16/3$ (from the previous part), we have $(16/3)/BF = 10/(8-BF)$. Therefore, we have $30BF = 128 - 16BF$, so $46BF = 128$, from which we have $BF = \boxed{64/23}$.

You're having a hard time with these problems...i spent weeks trying to solve these (i was doing these problems before you posted)

#14 Re: Help Me ! » Help with 2 questions » 2016-05-19 15:14:14

I want to calculate the angle right of the diagonal.

#15 Re: Help Me ! » HELP with 3 questions » 2016-05-19 15:12:26

I need help with
Randy presses RAND on his calculator twice to obtain two random numbers between 0 and 1. Let $p$ be the probability that these two numbers and 1 form the sides of an obtuse triangle. Find $4p$.

#16 Re: Help Me ! » Geometry Proof-HELP ASAP!! » 2016-05-19 14:17:19

Are you in sseraj's geometry class, because i have the same geometry question?

#18 Help Me ! » HELP with 3 questions » 2016-05-18 16:35:08

apsara123
Replies: 11

1.Kendra has an unlimited supply of unbreakable sticks of length 2, 4 and 6 inches. Using these sticks, how many non-congruent triangles can she make if each side is made with a whole stick? Two sticks can be joined only at a vertex of the triangle. (A triangle with sides of length 4, 6, 6 is an example of one such triangle to be included, whereas a triangle with sides of length 2, 2, 4 should not be included.)

2.Points $D$, $E$, and $F$ are the midpoints of sides $\overline{BC}$, $\overline{CA}$, and $\overline{AB}$ of $\triangle ABC$, respectively, and $\overline{CZ}$ is an altitude of the triangle. If $\angle BAC = 71^\circ$, $\angle ABC = 39^\circ$, and $\angle BCA = 70^\circ$, then what is $\angle EZD+\angle EFD$ in degrees?


3.In triangle $ABC$, the medians $\overline{AD}$, $\overline{BE}$, and $\overline{CF}$ concur at the centroid $G$.

(a) Prove that $AD < (AB + AC)/2$.

(b) Let $P=AB+AC+BC$ be the perimeter of $\triangle ABC.$ Prove that
\[\frac{3P}{4} < AD + BE + CF < P.\]

I need help with these 3 problems, thank you!!!

#19 Re: Help Me ! » Help with 2 questions » 2016-05-16 15:50:35

Sorry..I meant
The following diagonal is drawn in a regular heptagon, creating a pentagon and a quadrilateral. What is the measure of x? Express your answer as a common fraction.

#20 Help Me ! » Help with 2 questions » 2016-05-15 13:28:34

apsara123
Replies: 10

I need help with these 2 questions thanks

1.The diagonals of a regular hexagon have two possible lengths. What is the ratio of the shorter length to the longer length? Express your answer as a common fraction in simplest radical form.

2.The diagonals of a regular hexagon have two possible lengths. What is the ratio of the shorter length to the longer length? Express your answer as a common fraction in simplest radical form.

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