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2 years ago

How many chords are determined by joining dots on a circle

Mathematics

1 answer:

Aleonysh [2.5K]2 years ago

3 0

Answer:The calculation is that from each of the point a chord can be connected to the 7 other points… and that makes 56 chords.

Step-by-step explanation:

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I NEED HELP ASAP! THANKS :)

4vir4ik [10]

Answer:

Last option: increasing: -2 < x < 0 and x> 3/2;

decreasing: x < -2 and 0 < x < 3/2

Step-by-step explanation:

The function given is an absolute cubic function. (Pictured below).

We can determine from the graph that the equation increases over the interval:

increasing: -2 < x < 0 and x> 3/2;

decreasing: x < -2 and 0 < x < 3/2

6 0

3 years ago

Read 2 more answers

Match the circle equations in general form with their corresponding equations in standard form. Not all will be used.

Xelga [282]

The standard form of the equation of a circumference is given by the following expression:

 $(x-h)^{2}+(y-k)^{2}=r^{2} \\ \\ where \ (h, k) \ is \ the \ center \ of \ the \ circumference \ and \ r \ the \ radius$

On the other hand, the general form is given as follows:

 $x^{2}+y^{2}+Dx+Ey+F=0 \\ \\ where: \\ D=-2h, \ E=-2k, \ F=h^{2}+k^{2}-r^{2}$ 

In this way, we can order the mentioned equations as follows:

Equations in Standard Form:

 $\bold{a)} \ (x-6)^{2}+(y-4)^{2}=56 \\ \bold{b)} \ (x-2)^{2} + (y+6)^{2}=60 \\ \bold{c)} \ (x+2)^{2}+(y+3)^{2}=18 \\ \bold{d)} \ (x+1)^{2}+(y-6)^{2}=46$

Equations in General Form:

$\bold{1)} \ x^{2}+y^{2}-4x+12y-20=0 \\ \bold{2)} \ x^{2}+y^{2}+6x-8y-10=0 \\ \bold{3)} \ 3x^{2}+3y^{2}+12x+18y-15=0 \\ \\ If \ we \ divide \ this \ equation \ by \ 3, \ the \ equation \ becomes: \\ x^{2}+y^{2}+4x+6y-5=0 \\ \\ \bold{4)} \ 5x^{2}+5y^{2}-10x+20y-30=0 \\ \\ If \ we \ divide \ this \ equation \ by \ 5, \ the \ equation \ becomes: \\ x^{2}+y^{2}-2x+4y-6=0 \\ \\ \bold{5)} \ 2x^{2}+2y^{2}-24x-16y-8=0 \\ \\ If \ we \ divide \ this \ equation \ by \ 2, \ the \ equation \ becomes: \\ x^{2}+y^{2}-12x-8y-4=0$

$\bold{6)} \ x^{2}+y^{2}+2x-12y$

So let's match each equation:

$\bold{From \ a)} \\ \\ (h,k)=(6,4),\ r=2\sqrt{14} \\ D=-12, \ E=-8 \\ F=-4$

Then, its general form is:

$x^{2}+y^{2}-12x-8y-4=0$

First. a) matches 5) 

$\bold{From \ b)} \\ \\ (h,k)=(2,-6),\ r=2\sqrt{15} \\ D=-4, \ E=12 \\ F=-20$

Then, its general form is:

$x^{2}+y^{2}-4x+12y-20=0$

Second. b) matches 1) 

$\bold{From \ c)} \\ \\ (h,k)=(-2,-3),\ r=3\sqrt{2} \\ D=4, \ E=6 \\ F=-5$

Then, its general form is:

$x^{2}+y^{2}+4x+6y-5=0$

Third. c) matches 3)

$\bold{From \ d)} \\ \\ (h,k)=(-1,6),\ r=\sqrt{46} \\ D=2, \ E=-12, \ F=-9$

Then, its general form is: $x^{2}+y^{2}+2x-12y-9=0$

Fourth. d) matches 6)

6 0

3 years ago

Read 2 more answers

A set of four cards consists of two red cards and two black cards. The cards are shuffled thoroughly, and I am dealt two cards.

Delvig [45]

25% because if you have 4 cards which would equal 100% and you are dealt 2 you have a 25% chance of getting any of the 4. (25x4=100)
But, if you are talking about probability of color it would be 50% because if you have 2 red cards and the total deck is 4 cards, then that is already half of the deck. And if you have 2 black cards then that makes up the other half. but if you are talking individually like Red 1 and Red 2 and Black 1 and Black 2 separating them would create a 25% probability. So, x= 25% (infivudually) or 50% (by color)

4 0

3 years ago

Which two grids can be combined to represent 140%?

umka2103 [35]

Can you make the a bit more clear

3 0

3 years ago

Read 2 more answers

Simplify the expression. 13[6^2/(5^2-4^2)+9] 181 169 26 585

Zina [86]

So 5^2 -4^2 is 25-16 which is 9
6^2/9 is 36/9 which is 4 +9 is 13
13(13) is 169

7 0

3 years ago