1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Gnoma [55]
3 years ago
14

How can polygons be considered a subcategory of two-dimensional figures?

Mathematics
1 answer:
Helga [31]3 years ago
4 0
Yes; for example triangles, squares, and rectangle.
You might be interested in
A scientific calculator has 42 buttons. There are twice as many grey buttons as orange buttons. There are two more white buttons
Arlecino [84]

Answer:

x + 2x + 2x + 2 + 4x + 4 = 42

Step-by-step explanation:

Let us assume the number of orange buttons be x

So, the grey buttons be 2x

The white buttons would be 2x + 2

And the black buttons be 2(2x + 2) i.e. 4x + 4

Also the total is 42 buttons

So, the equation is

x + 2x + 2x + 2 + 4x + 4 = 42

5 0
3 years ago
Help. Me. Please. Pt1
sergejj [24]

Answer:

A

Step-by-step explanation:

X<Y means x is less than y-5 and you get A.

5 0
2 years ago
Read 2 more answers
What is zero of the polynomial and example
stich3 [128]
<span> Binomials and trinomials are two types of polynomials. The first has two terms and the second has three.</span>
8 0
3 years ago
3. Let A, B, C be sets and let ????: ???? → ???? and ????: ???? → ????be two functions. Prove or find a counterexample to each o
Fiesta28 [93]

Answer / Explanation

The question is incomplete. It can be found in search engines. However, kindly find the complete question below.

Question

(1) Give an example of functions f : A −→ B and g : B −→ C such that g ◦ f is injective but g is not  injective.

(2) Suppose that f : A −→ B and g : B −→ C are functions and that g ◦ f is surjective. Is it true  that f must be surjective? Is it true that g must be surjective? Justify your answers with either a  counterexample or a proof

Answer

(1) There are lots of correct answers. You can set A = {1}, B = {2, 3} and C = {4}. Then define f : A −→ B by f(1) = 2 and g : B −→ C by g(2) = 4 and g(3) = 4. Then g is not  injective (since both 2, 3 7→ 4) but g ◦ f is injective.  Here’s another correct answer using more familiar functions.

Let f : R≥0 −→ R be given by f(x) = √

x. Let g : R −→ R be given by g(x) = x , 2  . Then g is not  injective (since g(1) = g(−1)) but g ◦ f : R≥0 −→ R is injective since it sends x 7→ x.

NOTE: Lots of groups did some variant of the second example. I took off points if they didn’t  specify the domain and codomain though. Note that the codomain of f must equal the domain of

g for g ◦ f to make sense.

(2) Answer

Solution: There are two questions in this problem.

Must f be surjective? The answer is no. Indeed, let A = {1}, B = {2, 3} and C = {4}.  Then define f : A −→ B by f(1) = 2 and g : B −→ C by g(2) = 4 and g(3) = 4. We see that  g ◦ f : {1} −→ {4} is surjective (since 1 7→ 4) but f is certainly not surjective.  Must g be surjective? The answer is yes, here’s the proof. Suppose that c ∈ C is arbitrary (we  must find b ∈ B so that g(b) = c, at which point we will be done). Since g ◦ f is surjective, for the  c we have already fixed, there exists some a ∈ A such that c = (g ◦ f)(a) = g(f(a)). Let b := f(a).

Then g(b) = g(f(a)) = c and we have found our desired b.  Remark: It is good to compare the answer to this problem to the answer to the two problems

on the previous page.  The part of this problem most groups had the most issue with was the second. Everyone should  be comfortable with carefully proving a function is surjective by the time we get to the midterm.

3 0
3 years ago
2/3 a -1/6=1/3 <br> Solve the equation
Taya2010 [7]

Step-by-step explanation:

a=3/4

3 0
3 years ago
Other questions:
  • Tom took four seconds to run 6 yards Diane ran 5 yards in three seconds if they continue to run at the same speed who were to ge
    12·2 answers
  • If you spin the spinner 40 times ,how many 4’s?
    12·2 answers
  • Can the division expression 4÷15 be shown as a fraction? Why?
    15·2 answers
  • Find the value of the following.<br> (a) 180 % of 200g
    11·2 answers
  • Ayudemen porfavor . Determine 4 ala potencia x + 4 ala potencia -x, si se sabe que 2ala potencia x + 2 ala potencia -x =3
    13·1 answer
  • Matt wants to purchase a watch for $64.50. If there was a 25% discount and the tax rate was 7%, what was the total price that it
    12·2 answers
  • You have a new tv that is marked as a 56”. if the aspect ratio is 16:9 what is the height and width
    10·1 answer
  • Please help me with my maths prep...........
    9·1 answer
  • In the equation 2x + 3y = 19, what is the constant?
    8·1 answer
  • Is ac perpidicular to xz? explain
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!