A regular polygon is drawn in a circle so that each vertex is on the circle and is connected to the center by a radius.
Each of the central angles has a measure of 40°. How many sides does the polygon have?
THE
9
Answers
Answer: 90 sides
Step-by-step explanation:
Let's say the circle has a center at A and B and C are at the vertices of a polygon. Since this figure is inscribed in a circle, we can draw two radii through the vertices. Because all radii are congruent, we know segment BA is congruent to Segment CA. If a triangle has at least 2 congruent sides, we can identify the triangle as an isosceles triangle. With this we can conclude <ACB is congruent to <ABC. By the definition of congruent angles, m<ACB = M<ABC. Let's say m<ACB = x. By the Triangle Sum Theorem, 40 + x + m<ABC = 180. By substitution, 40 + x + x = 180. When we solve we get x =70. Since radii bisect interior angles we know that each interior angle of this polygon is 140 degrees. If we plug in 140 to our equation, [tex]\frac{(n-2)180}{n}[/tex] where n is the number of sides, we get n = 90. So we can conclude this polygon has 90 sides
Explanation
(7/2)-2=40
40*2
Related Questions
Meg is 6 years older than Victor. Meg's age is 2 years less than five times Victor's age. The equations below model the relationship between Meg's age (m) and Victor's age (v):
m = v + 6
m = 5v − 2
Which is a possible correct method to find Meg's and Victor's ages?
Solve m + 6 = 5m − 2 to find the value of m.
Write the points where the graphs of the equations intersect the x axis.
Solve v + 6 = 5v − 2 to find the value of v.
Write the points where the graphs of the equations intersect the y axis.
Answers
Answer:
Option C
Step-by-step explanation:
Step 1: Find the correct method
Option A is incorrect because we don't have m + 6 and 5m - 2
Option B is incorrect because that wouldn't show us the correct value
Option C is correct, once we solve for v, we can plug in v and get the value of m. For example: v + 6 = 5v - 2 → v + 8 = 5v → 8 = 4v → 2 = v. Then we plug it into the other equation m = 2 + 6 → m = 8
Option D is incorrect because that wouldn't show us the correct value.
Answer: Option C
The probability that Barry Bonds hits a home run on any given at-bat is 0.16, and each at-bat is independent.
Part A: What is the probability that the next home run will be on his fifth at-bat? (5 points)
Part B: What is the expected number of at-bats until the next home run? (5 points)
Answers
Answer:
a) 0.0797 = 7.97% probability that the next home run will be on his fifth at-bat.
b) The expected number of at-bats until the next home run is 6.25.
Step-by-step explanation:
For each at bat, there are two possible outcomes. Either it is a home run, or it is not. The probability of an at bat resulting in a home run is independent of any other at-bat, which means that the binomial probability distribution is used to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
And p is the probability of X happening.
The probability that Barry Bonds hits a home run on any given at-bat is 0.16
This means that [tex]p = 0.16[/tex]
Part A: What is the probability that the next home run will be on his fifth at-bat?
0 on his next 4(P(X = 0) when n = 4)
Home run on his 5th at-bat, with 0.16 probability. So
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 0) = C_{4,0}.(0.16)^{0}.(0.84)^{4} = 0.49787136 [/tex]
0.49787136 *0.16 = 0.0797.
0.0797 = 7.97% probability that the next home run will be on his fifth at-bat.
Part B: What is the expected number of at-bats until the next home run?
The expected number of trials for n successes is given by:
[tex]E = \frac{n}{p}[/tex]
In this question, [tex]n = 1, p = 0.16[/tex]. So
[tex]E = \frac{1}{0.16} = 6.25[/tex]
The expected number of at-bats until the next home run is 6.25.
Help pls I need to pass
Answers
Answer:
u still doing school :)
Step-by-step explanation:
find all complex numbers z such that z^2=2i
please answer in a+bi
thank you
Answers
2 Answers:
z = 1 + i and z = -1 - i
========================================================
Explanation:
We want z to be a complex number in the form z = a+bi, where a,b are real numbers and [tex]i = \sqrt{-1}[/tex] is imaginary.
Let's plug that into the equation your teacher gave you
[tex]z^2 = 2i\\\\(a+bi)^2 = 2i\\\\(a+bi)(a+bi) = 2i\\\\a(a+bi)+bi(a+bi) = 2i\\\\a^2+abi+abi+b^2*i^2 = 2i\\\\a^2+2abi+b^2*(-1) = 2i\\\\a^2+2abi-b^2 = 2i\\\\(a^2-b^2)+2abi = 0+2i\\\\[/tex]
You could use the FOIL rule to take a shortcut. I'm deciding to be a bit more wordy to show a further breakdown how everything is multiplying out.
Notice that the real part a^2-b^2 must be 0 so that it matches the real part on the right hand side.
a^2-b^2 = 0
(a-b)(a+b) = 0 .... difference of squares rule
a-b = 0 or a+b = 0
a = b or a = -b
So whatever solution z = a+bi is, it must have either a = b or a = -b.
--------------------------------
If a = b, then the 2abi portion on the left side turns into 2a^2*i
Set this equal to 2i on the right hand side and isolate 'a'
[tex]2a^2*i = 2i\\\\2a^2 = 2\\\\a^2 = 1\\\\a = 1 \text{ or } a = -1\\\\[/tex]
So a = 1 leads to b = 1
Or a = -1 leads to b = -1
Two complex solutions so far are: z = 1 + i and z = -1 - i based on those two cases above.
--------------------------------
Now consider the case that a = -b
We'll effectively have the same steps as the previous section, but the equation to solve now is [tex]-2a^2*i = 2i\\\\[/tex]
The only difference is that negative is out front. You should find that it leads to a^2 = -1, but this has no solutions because we stated earlier that a,b were real numbers.
So if a = -b, then it concludes with a,b being nonreal numbers. Ultimately we rule out the case that a = -b is possible.
Put another way, note how -2a^2 is always negative which clashes with the idea that the right hand side is positive (ignore the 'i' portions). This contradiction means that no real values of 'a' will make the equation [tex]-2a^2*i = 2i\\\\[/tex] to be true.
--------------------------------
To wrap things up, we only have two solutions and they are
z = 1 + i and z = -1 - i
You can use a tool like WolframAlpha to confirm this.
How many spaces does it move over
Answers
Answer:
The point at the bottom has to move over 2 to the left to be aligned with the point at the top however they will have a 3 space in between the 2 same for the point at the top, the top point moves over 2 to the right to be aligned with the bottom point, then they will have a 3 square space between each other.
Answer:Around 3 spaces between?
Step-by-step explanation:
A department store mails a customer satisfaction survey to people who make credit card purchases at the store. This month, 3521 people made credit card purchases. Surveys are mailed to 278 of these people, chosen at random, and 172 people return the survey form. Identify the population and the sample.
Answers
Answer:
The population is the population of 3521 people who made credit card purchases.
The sample is the 172 people who returned the survey form.
Step-by-step explanation:
Department mails customers satisfactions forms to those who make credit cards purchase at the store, totaling 3521 people. Thus, the population is the population of 3521 people who made credit card purchases.
Surveys are mailed to 278 of these people, chosen at random, and 172 people return the survey form.
Thus the sample, that is, those from whom the data will be taken and expanded to the rest of the population, is the 172 people who returned the survey form.
The population is all 3521 people who made credit card purchases.
The sample is the 172 people who returned the survey form.
1+log2=log(x+1)
I know that x=19 but how do you get 19?
Answers
Step-by-step explanation:
Recall that [tex]\log 10 = 1[/tex] so we can rewrite the equation above as
[tex]\log 10 + \log 2 = \log (x + 1)[/tex]
Also recall that [tex]\log(ab) = \log a + \log b[/tex] so the left-hand side becomes
[tex]\log [(10)(2)] = \log (x + 1)[/tex]
or
[tex]20 = x + 1 \Rightarrow x = 19[/tex]
Find RS. Can anyone help?
Answers
The segment XT splits the trapezoid exactly in half. The average of RS and Q will give us XT because of the properties of a trapezoid.
We find the area of a trapezoid by averaging the bases as well.
RS + Q / 2 = XT
RS + 26 / 2 = 22
RS + 26 = 44
RS = 18
Hope this helps!
Linda leaves the school to go home. She walks 7 blocks south and then 9 blocks east. how far is Linda from her office?
A.8 blocks
B.11.5 blocks
C.20 blocks
D.14 blocks
Answers
Answer:
B. 11.5
Step-by-step explanation:
That missing length can be solved via the equation a^2+b^2=c^2, where the hypotenuse is c. We know A and B, which is 7 and 9.
7^2+9^2=130
sqrt 130 is 11.4017543
Here, you kinda have to break the rules of rounding to say that it is B.
There could be a more efficient route for resolving this answer, but this is the method that I was taught.
Kenji simplifies 3^5 x 4^ 5and gets the result 12^10, but Darlene is not sure. Is Kenji correct? Justify your answer.
Answers
That's a question about exponentiation.
Answer:
Kenji is wrong because he does not aply the porperty correctly.
Step-by-step explanation:
A exponetiation has this form:
[tex]\boxed{a^b}[/tex]
a is the base
b is the power or exponent
To understand that situation it's important to know a property about exponentiation. When we have a multiplication with the same exponent and diferent bases, the result is the multiplication of the bases with the same exponent. Let's see this above, in mathematical language:
[tex]\boxed{a^b \cdot c^b = (a\cdot c) ^b}[/tex]
Examples:
[tex]2^3 \cdot 8^3 = (2 \cdot 8) ^3 = 16^3[/tex][tex]10^9 \cdot 23^9 = (10 \cdot 23) ^9 = 230^9[/tex]Now, we can say why Kenji is wrong. It's easy simplify [tex]3^5 \cdot 4^5[/tex]! We know that the result is [tex](3 \cdot 4) ^5 = 12^5[/tex], but Kenji multiplied the bases and added the exponents, that's why he is wrong.
I hope I've helped. ^^
Enjoy your studies! \o/
T is the midpoint of pq where pt=3x-3 and tq=5x-7 find x
Answers
Answer: x = 2
Step-by-step explanation:
P-----------------------T----------------------Q
(3x-3) (5x-7)
Since T is the midpoint we know that PT and TQ are equal
Just solve the equation: 3x-3 = 5x-7
[tex]3x-3 = 5x-7[/tex]
now move the x to one side
[tex]-3 = 2x-7[/tex] (I subtracted the 3x)
then get the 2x by itself
[tex]4=2x[/tex]
lastly, divide by 2 to get x by itself
[tex]x=2\\[/tex]
what is the radius of a circle in it in if the area is 36m²?
A.0.339 m
B.3.39 m
C.78.5 m²
D.339 m
Answers
Answer:
B. 3.39 m
Step-by-step explanation:
r² = A/π
= 36/3.14
= 11.465
r = √11.465 = 3.39
The following expression gives an approximate value of the total average credit card debt in a U.S. household (in dollars) t years after 1995.
400t + 5750
Use this expression to predict what the total average credit card debt will be in the year 2025.
Answer: In the year 2025, the total average credit card debt for a U.S. household will be ------------ dollars.
Answers
Answer:
In 2025, t=30. so D=418*30+6000 = 18540
Bobby wants to bring popsicles to a summer barbecue. He decides to try a new recipe for pineapple-orange popsicles, so he makes a small batch with 1 cup of pineapple juice and 3 cups of orange juice to taste. He likes the combination, so he uses 3 cups of pineapple juice and 7 cups of orange juice to make a larger batch for the barbecue. Which batch of popsicles tastes more like oranges?
Answers
Answer:The first would taste more like oranges
Step-by-step explanation:
For a two-tailed test with a sample size of 20 and a .20 level of significance, the t value is _____. Selected Answer: d. 1.328
Answers
Answer:
1.328
Step-by-step explanation:
Given :
Sample size, n = 20.
Degree of freedom, df = n - 1
df = 20 - 1 = 19
α = 0.2
Using the T-distribution calculator :
Since it is two - tailed:
Tα/2 ; 19 = T0.2/2 ; 19 = T0.1, 19 = 1.3277 = 1.328
Using a t-distribution calculator, it is found that the t-value is of t = 1.328.
How to find the critical value of the t-distribution?In a calculator, these following inputs are needed:
The number of degrees of freedom, which is one less than the sample size.The level of significance.Whether the test is one-tailed or two-tailed.In this problem, inputting the data given in a calculator, it is found that the t-value is of t = 1.328.
More can be learned about the t-distribution at https://brainly.com/question/13873630
jill number has a prime factorization with 6 numbers. Jamal number had a prime factorization with 3 numbers. Whos is bigger. jill says hers is but jamal jays not true explain.
Answers
Answer:
not enough information
Step-by-step explanation:
jill could have 2*2*2*2*2*2
and Jamal 113*113*113
but if Jill's number is made from all high primes and Jamals from low ones, it's vice versa
Use the Chain Rule to find dw/dt.
w = xey/z, x = t3, y = 7 − t, z = 8 + 4t
dw
dt
=
Answers
[tex] \frac{dw}{dt} = \frac{dx}{dt} \times \frac{dw}{dx} + \frac{dy}{dt} \times \frac{dw}{dy} + \frac{dz}{dt} \times \frac{dw}{dz} \\ \frac{dw}{dt} = 3t ^{2} \times {e}^{ \frac{y}{z} } + - t \times \frac{x {e}^{ \frac{y}{z} } }{z} + 4 \times - \frac{xy {e}^{ \frac{y}{z} } }{ {z}^{2} } \\ \frac{dw}{dt} = \frac{ {e}^{ \frac{y}{z} } (3 {t}^{2} {z}^{2} - tzx - 4xy)}{ {z}^{2} } [/tex]
what is the length of a rectangular solid with a volume of 180 cu ft, if it is 9 ft high and 4ft wide?
Answers
Answer:
5 ft
Step-by-step explanation:
The formula for Volume is V=lwh, or Volume = length x width x height.
The equation would be:
[tex]180=l(4)(9)[/tex]
or
[tex]180=36l[/tex]
To find the answer, divide by 36.
[tex]\frac{180}{36} =\frac{36l}{36}[/tex]
[tex]5=l[/tex]
The real answer is really 280
Two cars started from the same town at the same time. One car traveled 50 miles an hour for 4 hours. The other car traveled 60 miles an hour for 8 hours. How many miles farther did the second car travel?
10
40
200
280
Answers
Answer:
The second car traveled 280 miles farther than the first car.
Step-by-step explanation:
Car A: 50 mi/1 hr for 4 hrs
Car B: 60 mi/1 hr for 8 hrs
Solve for Car A:
50 mi/1 hr × 4 hrs
50 × 4
200 miles
Solve for Car B:
60 mi/1 hr × 8 hrs
60 × 8
480 miles
Find the difference between Car A and Car B:
480 miles - 200 miles
280 miles
Find the missing pieces of the triangle round to the nearest tenth
Answers
Answer:
8√3
Step-by-step explanation:
Missing side,
√(19²-13³)
= 8√3
Answered by GAUTHMATH
Ten pairs of points yielded a correlation coefficient r of 0.790. If a =0.05, which of the following statements is correct if H.: P = 0? (Do not calculate a t-value.) A) Because 0.790 is greater than 0.632, the nullliy pothesis is not rejected. Because 0.790 is greater than 0.602, che null hypothesis is not rejected. Because 0.790 is greater than 0.632, che null hypothesis is rejected. OD) There is no correlation between the variables
Answers
Step-by-step explanation:
Ten pairs of points yielded a correlation coefficient r of 0.790. If a =0.05, which of the following statements is correct if H.: P = 0? (Do not calculate a t-value.) A) Because 0.790 is greater than 0.632, the nullliy pothesis is not rejected. Because 0.790 is greater than 0.602, che null hypothesis is not rejected. Because 0.790 is greater than 0.632, che null hypothesis is rejected. OD) There is no correlation between the variables
Given the parabola below, find the endpoints of the latus rectum. (x-2)^2=-20(y+2)
Answers
Answer:
The endpoints of the latus rectum are [tex](12, -7)[/tex] and [tex](-8, -7)[/tex].
Step-by-step explanation:
A parabola with vertex at point [tex]C(x, y) = (h,k)[/tex] and whose axis of symmetry is parallel to the y-axis is defined by the following formula:
[tex](x-h)^{2} = 4\cdot p \cdot (y-k)[/tex] (1)
Where:
[tex]y[/tex] - Independent variable.
[tex]x[/tex] - Dependent variable.
[tex]p[/tex] - Distance from vertex to the focus.
[tex]h[/tex], [tex]k[/tex] - Coordinates of the vertex.
The coordinates of the focus are represented by:
[tex]F(x,y) = (h, k+p)[/tex] (2)
The latus rectum is a line segment parallel to the x-axis which contains the focus. If we know that [tex]h = 2[/tex], [tex]k = -2[/tex] and [tex]p = -5[/tex], then the latus rectum is between the following endpoints:
By (2):
[tex]F(x,y) = (2, -2-5)[/tex]
[tex]F(x,y) = (2,-7)[/tex]
By (1):
[tex](x-2)^{2} = -20\cdot (-7+2)[/tex]
[tex](x-2)^{2} = 100[/tex]
[tex]x - 2 = \pm 10[/tex]
There are two solutions:
[tex]x_{1} = 2 + 10[/tex]
[tex]x_{1} = 12[/tex]
[tex]x_{2} = 2-10[/tex]
[tex]x_{2} = -8[/tex]
Hence, the endpoints of the latus rectum are [tex](12, -7)[/tex] and [tex](-8, -7)[/tex].
A technology company is forming a task force of six members to deal with urgent quality issues. The positions will be filled by randomly chosen qualified applicants. The qualified applicants consist of five managers and ten engineers.
Required:
a. What is the probability that the chosen applicants are either all managers or all engineers?
b. What is the probability that the number of managers is the same as the number of engineers on the task force?
c. What is the expected number of engineers chosen?
d. What is the probability that at least one manager is chosen for the task force?
Answers
Answer:
a. 0.042 = 4.2% probability that the chosen applicants are either all managers or all engineers.
b. 0.2398 = 23.98% probability that the number of managers is the same as the number of engineers on the task force.
c. The expected number of engineers chosen is 4.
d. 0.958 = 95.8% probability that at least one manager is chosen for the task force.
Step-by-step explanation:
The positions are chosen without replacement, which means that the hypergeometric distribution is used to solve this question.
Hypergeometric distribution:
The probability of x successes is given by the following formula:
[tex]P(X = x) = h(x,N,n,k) = \frac{C_{k,x}*C_{N-k,n-x}}{C_{N,n}}[/tex]
In which:
x is the number of successes.
N is the size of the population.
n is the size of the sample.
k is the total number of desired outcomes.
Combinations formula:
[tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
In this question:
5 + 10 = 15 applicants, which means that [tex]N = 15[/tex]
10 are engineers, which means that [tex]k = 10[/tex]
Six members are chosen, which means that [tex]k = 6[/tex]
a. What is the probability that the chosen applicants are either all managers or all engineers?
Not possible having all managers(five applicants are manager, while there are 6 open positions), so this is P(X = 6), that is, all engineers.
[tex]P(X = x) = h(x,N,n,k) = \frac{C_{k,x}*C_{N-k,n-x}}{C_{N,n}}[/tex]
[tex]P(X = 6) = h(6,15,6,10) = \frac{C_{10,6}*C_{5,0}}{C_{15,6}} = 0.042[/tex]
0.042 = 4.2% probability that the chosen applicants are either all managers or all engineers.
b. What is the probability that the number of managers is the same as the number of engineers on the task force?
3 engineers, so this is P(X = 3).
[tex]P(X = x) = h(x,N,n,k) = \frac{C_{k,x}*C_{N-k,n-x}}{C_{N,n}}[/tex]
[tex]P(X = 3) = h(3,15,6,10) = \frac{C_{10,3}*C_{5,3}}{C_{15,6}} = 0.2398[/tex]
0.2398 = 23.98% probability that the number of managers is the same as the number of engineers on the task force.
c. What is the expected number of engineers chosen?
The expected value of the hypergeometric distribution is:
[tex]E(X) = \frac{nk}{N}[/tex]
So
[tex]E(X) = \frac{6(10)}{15} = 4[/tex]
The expected number of engineers chosen is 4.
d. What is the probability that at least one manager is chosen for the task force?
At most five engineers, which is:
[tex]P(X \leq 5) = 1 - P(X = 6)[/tex]
Since in item a. we already have P(X = 6).
[tex]P(X \leq 5) = 1 - 0.042 = 0.958[/tex]
0.958 = 95.8% probability that at least one manager is chosen for the task force.
. In Habib High School 275 of 300 students received a grade of A, while in Public Hall 120 out of 150 students received a grade of A. Which of the two schools has a better record?
Answers
Which function is represented by the graph?
f(x) = −|x − 3| + 4
f(x) = −|x + 3| + 4
f(x) = −|x − 4| + 3
f(x) = −|x + 4| + 3
Answers
1) has vertex (3,4)
2)has vertex (-3,4)
3)has vertex (4,3)
4)has vertex(-4,3)
The functions should look the same, the only difference is the vertex.
What is the equation of the midline for the function f(x)?
f(x)=12sin(x)+3
Enter your answer in the box.
Answers
9514 1404 393
Answer:
f(x) = 3
Step-by-step explanation:
Replace sin(x) with 0 and you will have it.
f(x) = 12·0 +3
f(x) = 3
Answer:
y= 3
Step-by-step explanation:
I took the test
What are the zeroes of f(x) = x2 - X - 2?
x= -2,1
x = 2, -1
x= -2, -1
x = 2,1
Answers
Answer:
x=2 x=-1
Step-by-step explanation:
f(x) = x^2 - X - 2
0= x^2 -x-2
Factor
0 =(x-2)(x+1)
Using the zero product property
x-2 =0 x+1 =0
x=2 x=-1
Answer:
x=2, -1
Step-by-step explanation:
Hi there!
We want to find the zeros of this function: f(x)=x²-x-2
The zeros are the values of x that will make f(x)=0
So that means in order to find the zeros, set f(x) as 0
In that case,
x²-x-2=0
Now let's solve the quadratic equation
We can do it by factoring
-x is the sum of two numbers, while -2 is the product of those two same numbers
Now think: which two numbers add up to -1, but multiply to get -2?
Those numbers are -2 and 1
Now factor the polynomial by FOIL:
(x-2)(x+1)=0
Split and solve
x-2=0
x=2
x+1=0
x=-1
The zeros are x=2, -1
Hope this helps!
Bus X and bus y traveled the same 80-mile route. If bus X took 2 hours and bus y traveled at an average speed that was 50 percent faster than the average speed of bus X, how many hours did bus y take to travel the route?
Answers
Answer:
1 hr , 18 mins
Step-by-step explanation:
that is the procedure above
By which number should (2/5)^-3 be multiplied to get (1/2)^4 as a product ?
Answers
Answer:
[tex]\frac{2}{5}^{-3}[/tex]×[tex]x=\frac{1}{2}^{4}[/tex]
[tex]x=\frac{2}{5} ^{3} \\[/tex]×[tex]\frac{1}{2}^{4}[/tex]
(negative in the exponent means reciprocal of the fraction)
x= [tex]\frac{1}{250}[/tex]
Brainliest please
Find the solution(s) of the system of equations. y = x2 + 4x y + x2 = –4x Question 7 options: A) (–4, 0) and (0, 0) B) (0, 0) C) (–4, 0) and (4, 0) D) (0, 0) and (4, 0)
Answers
Answer:
Hello,
Answer A (-4,0) and (0,0)
Step-by-step explanation:
[tex]\left\{\begin{array}{ccc}y&=&x^2+4x\\y+x^2&=&-4x\\\end{array} \right.\\\\\\\left\{\begin{array}{ccc}y&=&x^2+4x\\y&=&-x^2-4x\\\end{array} \right.\\\\\\\left\{\begin{array}{ccc}y&=&x^2+4x\\x^2+4x&=&-x^2-4x\\\end{array} \right.\\\\\\\left\{\begin{array}{ccc}2*x^2+8*x&=&0\\y&=&x^2+4x\\\end{array} \right.\\\\\\\left\{\begin{array}{ccc}x(x+4)&=&0\\y&=&x^2+4x\\\end{array} \right.\\\\\\[/tex]
[tex]\left\{\begin{array}{ccc}x&=&0 \\y&=&0\\\end{array} \right. \ or\ \left\{\begin{array}{ccc}x&=&-4 \\y&=&0\\\end{array} \right.[/tex]
