En las olimpiadas de Matemática. Roció represen a su colegio. La prueba consistía en 60 problemas. Cada respuesta correcta valía 4 puntos y por cada respuesta incorrecta había un punto en contra. Luego del examen. Roció obtuvo un puntaje de 155. Ella respondió todas las preguntas y desea saber cuantas fueron correctas y cuantas incorrectas

Answer:

which grade are you in so that i can tell you according to that

i, vì AD//BC nên góc A +góc B =180°

ii, góc A=góc B nên góc C=góc D -> ABCD là hình bình hành

And AB=BC=> ABCD là hình thoi

Answer:

13.41

Step-by-step explanation:

Hope it helps!

Answer:

6[tex]\sqrt{5}[/tex]

Step-by-step explanation:

Using the rule of radicals

[tex]\sqrt{a}[/tex] × [tex]\sqrt{b}[/tex] ⇔ [tex]\sqrt{ab}[/tex]

Simplifying the radicals

[tex]\sqrt{20}[/tex]

= [tex]\sqrt{4(5)}[/tex]

= [tex]\sqrt{4}[/tex] × [tex]\sqrt{5}[/tex] = 2[tex]\sqrt{5}[/tex]

[tex]\sqrt{80}[/tex]

= [tex]\sqrt{16(5)}[/tex]

= [tex]\sqrt{16}[/tex] × [tex]\sqrt{5}[/tex] = 4[tex]\sqrt{5}[/tex]

Then

[tex]\sqrt{20}[/tex] + [tex]\sqrt{80}[/tex]

= 2[tex]\sqrt{5}[/tex] + 4[tex]\sqrt{5}[/tex]

= 6[tex]\sqrt{5}[/tex]

Answer:

3/10

Step-by-step explanation:

3 red, 4 green, and 3 yellow balls = 10 balls

P(red) = number of red balls / total balls

           = 3/10

Answer:

a=15

Step-by-step explanation:

3a+b = 54

Let b=9

3a+9 = 54

Subtract 9 from each side

3a+9-9= 54-9

3a = 45

Divide each side by 3

3a/3 = 45/3

a = 15

Answer:

[tex]3a+b=54[/tex]

[tex]3a+9=54\:[b=9][/tex]

[tex]3a=54-9[/tex]

Subtract 9 from both sides

[tex]3a=45[/tex]

Divide both sides by 3

[tex]\frac{3a}{3}=\frac{45}{3}[/tex]

[tex]a=15[/tex]

OAmalOHopeO

Step-by-step explanation:

1/sin^2A -cos^2A/sin^2 A. ~tan = sin/cos

(1-cos^2)/sin^2A. ~ take lcm

sin^2A/sin^ A. ~ 1-cos^2A = sin^2A

1

for more free ans check bio

Answer:

[tex]\displaystyle \frac{1}{\sin^2x}-\frac{1}{\tan^2x}=1[/tex]

Step-by-step explanation:

Prove that:

[tex]\displaystyle \frac{1}{\sin^2x}-\frac{1}{\tan^2x}=1[/tex]

Recall that by definition:

[tex]\displaystyle \tan x=\frac{\sin x}{\cos x}[/tex]

Therefore,

[tex]\displaystyle \tan^2x=\left (\frac{\sin^2x}{\cos^2x}\right)^2=\frac{\sin^2x}{\cos^2x}[/tex]

Substitute [tex]\displaystyle \tan^2x=\frac{\sin^2x}{\cos^2x}[/tex] into [tex]\displaystyle \frac{1}{\sin^2x}-\frac{1}{\tan^2x}=1[/tex]:

[tex]\displaystyle \frac{1}{\sin^2x}-\frac{1}{\frac{\sin^2x}{\cos^2x}}=1[/tex]

Simplify:

[tex]\displaystyle \frac{1}{\sin^2x}-\frac{\cos^2x}{\sin^2x}=1[/tex]

Combine like terms:

[tex]\displaystyle \frac{1-\cos^2x}{\sin^2x}=1[/tex]

Recall the following Pythagorean Identity:

[tex]\sin^2x+\cos^2x=1[/tex] (derived from the Pythagorean Theorem)

Subtract [tex]\cos^2x[/tex] from both sides:

[tex]\sin^2=1-\cos^2x[/tex]

Finish by substituting [tex]\sin^2=1-\cos^2x[/tex] into [tex]\displaystyle \frac{1-\cos^2x}{\sin^2x}=1[/tex]:

[tex]\displaystyle \frac{\sin^2x}{\sin^2x}=1,\\\\1=1\:\boxed{\checkmark\text{ True}}[/tex]

Answer:

B=.5*8*6=.5*48=24

h = 8

P=10+6+8=24

Surface area =2*24+24*8=48+192=240

Step-by-step explanation:

The base is a triangle, and the area of a triangle is 1/2 base (or width) times height (or length). In this case, base is 8 and height is 6, so the area can be found either by multiplying .5*8*6 or by dividing 8*6 by 2, either of which will give you the same answer of B=24.

Height is given, h=8.

Perimeter is simply the sum of the sides, which are given, so the perimeter is 8+6+10=24.

The formula for surface area is given, so all you need to do is plug in your previous answers and you've got it!

Answer:

d = p + 85

Step-by-step explanation:

We don't have a lot to go on for this problem. We have two undefined variables.

In order to solve for d, we need to isolate it:

d - 85 = p

Add 85 to both sides

d = p + 85

Answer: [tex]\left | 2t-5\right |,\ 2,\ 2t-5[/tex]

Step-by-step explanation:

Given

Position of the particle moving along the coordinate axis is given by

[tex]s(t)=t^2-5t+1[/tex]

Speed of the particle is given by

[tex]\Rightarrow v=\dfrac{ds}{dt}\\\\\Rightarrow v=\dfrac{d(t^2-5t+1)}{dt}\\\\\Rightarrow v=\left | 2t-5\right |[/tex]

Acceleration of the particle is

[tex]\Rightarrow a=\dfrac{dv}{dt}\\\\\Rightarrow a=2[/tex]

velocity can be negative, but speed cannot

[tex]\Rightarrow v=\dfrac{ds}{dt}\\\\\Rightarrow v=\dfrac{d(t^2-5t+1)}{dt}\\\\\Rightarrow v=2t-5[/tex]

Answer:

The area of tarpaulin is 1315.63 ft^2.  

Step-by-step explanation:

height, h = 20 feet

circumference, C = 102 feet

Let the radius is r.

Circumference, C = 2 x 3.14 x r = 102

r = 16.24 feet

Let the slant height is L.

[tex]L = \sqrt{h^2 + r^2}\\\\L = \sqrt{20^2 + 16.24^2}\\\\L = 25.8 ft[/tex]

The curved surface area is

S = 3.14 x r x L

S = 3.14 x 16.24 x 25.8 = 1315.63 ft^2

Answer:

400pi square feet

Step-by-step explanation:

Find the radius

Find the slant height

Put it in the formula for a cone but take the circumference part out

Divide your answer by pi

The question asks for the closest answer

400pi square feet is the closest option to 418.17pi square feet.

Answer:

Step-by-step explanation:

The vertices lie on the x-axis, as is determined by their coordinates. This makes the center of this hyperbola (0, 0) because the center is directly between the vertices. The fact that the foci also lie on the x-axis tells us that this is the main axis. What this also tells us is which way the hyperbola "opens". This one opens to the left and the right as opposed to up and down. The standard form for this hyperbola is:

[tex]\frac{(x-h)^2}{a^2}-\frac{(y-k)^2}{b^2}=1[/tex] and so far we have that h = 0 and k = 0.

By definition, a is the distance between the center and the vertices. So a = 5, and a-squared is 25. So we're getting there. Now here's the tricky part.

The expressions for the foci are (h-c, k) and (h+c, k). Since we know the foci lie at +/-13, we can use that to solve for c:

If h+c = 13 and h = 0, then

0 + c = 13 and c = 13.

We need that c value to help us find b:

[tex]c^2=a^2+b^2[/tex] and

[tex]13^2=5^2+b^2[/tex] and

[tex]169=25+b^2[/tex] and

[tex]144=b^2[/tex] so

b = 12. Now we're ready to fill in the equation:

[tex]\frac{x^2}{25}-\frac{y^2}{144}=1[/tex] and there you go!

Answer:

Step-by-step explanation:

6cos^2(x) + 7cos(x) +2 = 0

Call cos(x) = y to change this to something a little bit more familiar.

6y^2 + 7y + 2 =0

This equation is a quadratic. Solve it first. Then we'll go back to solving for cos(x)

This equation factors into 2 possible answers

(3y + 2)(2y + 1) = 0

3y + 2  = 0

3y = - 2

y = - 2/3

2y + 1 = 0

2y = - 1

y = - 1/2

Now let's start with

cos(x) = - 1/2

That means that x is in quadrant two or three.

cos-1(1/2) = 60 degrees.

Quad 2: x = 180 - 60 =  120

Quad 3: x = 180 + 60 =  240

Now cos(x) = - 2/3

cos-1(2/3) = 48.19

Quad 2: x = 180 - 48.19 = 131.81

Quad 3: x  = 180 + 48.19 = 228.19

Answer:

Step-by-step explanation:

29/9 or 3 2/9

Answer:

3560 people.

Step-by-step explanation:

You have to do 89% × 4000.

Or 0.89×4000=3560.

So 3560 is the answer.

Answer:

x = 18

Step-by-step explanation:

First, let's find the ratios between the two triangles

We'll use AV and AC

372 ÷ 589 = 12/19

All of the sides of the smaller triangle are 12/19 of the bigger triangle

Now let's find x

We know that AU + UB = AB

So it's 20x + 108 + 273 = AB

12/19 of a bigger triangle side equals a small triangle side

(12/19)AB = AU

For this equation multiply both sides by 19/12 to isolate AB

(12/19)AB x 19/12 = AU x 19/12

AB = (19/12)AU

Now we have this

20x + 108 + 273 = (19/12)(20x + 108)

20x + 381 = (19/12)(20x + 108)

Distribute the 19/12

20x + 381 = 95/3x + 171

Move all like terms to one side

20x + 381 = 95/3x + 171

       - 171                 - 171

20x + 210 = 95/3x

- 20x           - 20x

Don't forget about common denominators

210 = 95/3x - 60/3x

210 = 35/3x

Multiply both sides by 3

210 x 3 = 35/3x x 3

630 = 35x

Divide both sides by 35

630/35 = 35x/35

x = 18

Answer:

Step-by-step explanation:

[tex]\frac{20x+108}{20x+381}[/tex] = [tex]\frac{372}{589}[/tex]

589( 20x + 108 ) = 372( 20x + 381 )

11780x + 63612 = 7440x + 141732

4340x = 78120

x = 18

Answer: 17

Step-by-step explanation:

Using Pemdas, simplify the exponents, and then solve the multiplication and division inside the parentheses before subtracting. 10-9 = 1 so 1*7 =7

10 +7 is 17.

also i hope this helps and i hope this is not a test...

Answer:

n=1/8

Step-by-step explanation:

-8n+34=6(5+4n)

We move all terms to the left:

-8n+34-(6(5+4n))=0

We add all the numbers together, and all the variables

-8n-(6(4n+5))+34=0

We calculate terms in parentheses: -(6(4n+5)), so:

6(4n+5)

We multiply parentheses

24n+30

Back to the equation:

-(24n+30)

We get rid of parentheses

-8n-24n-30+34=0

We add all the numbers together, and all the variables

-32n+4=0

We move all terms containing n to the left, all other terms to the right

-32n=-4

n=-4/-32

n=1/8

Answer:

n= 0.125 or 1/8

Step-by-step explanation:

Distrubute 6 into (5+4n). It should give you 30+24n.

The equation should now look like this: -8n+34=30+24n.

Swap -8n with 30, giving -30+34=8n+24n. Add the numbers and the pronumerals together.

Now it will look like 4=32n. Divide the numbers, but unfortunately the number is small so the answer will have to be a decimal or a fraction. So it's 0.125 or 1/8.

If I didn't explain everything or something is wrong, please comment. I just signed up, so it's my first time using this.

c. 1600

1200 : 3 * 4

= 400 * 4

= 1600

The capacity of this coliseum is 1600

The correct option is (C)

A fraction is a part of a whole. In arithmetic, the number is expressed as a quotient, in which the numerator is divided by the denominator. In a simple fraction, both are integers. A complex fraction has a fraction in the numerator or denominator.

Given:

Total people attended the Coliseum= 1200

let he capacity be x

3/4*x= 1200

x= 1200*4/3

x= 1600

Learn more about fraction here:

https://brainly.com/question/10354322

#SPJ6

Your question is incomplete/other language, probably the traslated question/missing part is:

In a city coliseum, the final of a volleyball championship was played. In total, 1,200 people attended the Coliseum. this number of people represents 3/4 of its capacity. What is the capacity of this coliseum?

Answer:

Step-by-step explanation:

Answer:

Step-by-step explanation:11/2x(8-4)=22

Answer:

2

Step-by-step explanation:

We can use the slope formula

m = ( y2-y1)/(x2-x1)

m = ( 8-2)/(3-0)

   = 6/3

   = 2

Answer:

2

Brainliest, please!

Step-by-step explanation:

(0, 2)(3, 8)

y = +6

x = +3

y/x = 6/3 = 2

9514 1404 393

Answer:

  about 79 ft

Step-by-step explanation:

The relevant trig relation is ...

  Tan = Opposite/Adjacent

In this scenario, the angle is 23°, the adjacent side is the distance to the building, and the opposite side is the building height. Then we have ...

  height = tan(23°)·(186 ft) ≈ 78.95 ft ≈ 79 ft

Vì tam giác ABC cân tại A (gt) mà AM là đg trung tuyến nên AM đồng thời là đg cao của t/giác đó:

AM là trung tuyến của t/giác ABC nên M là trung điểm BC:

=> BM =BC/2 =6:2=3(cm)

Xét tam giác AMB vuông tại M

AB^2 =AM^2+BM^2 ( theo định lý Py-ta -go)

Answer:

the answer is B.

Step-by-step explanation:

it is not A is because if the radius is 6 then the volume will be 904.32

the answer is B.

because is the radius is 2 cm then the area I calculate with this radius is 33.4933333333 and the question want the approximate radius and out of all the numbers this one is the closest so the answer is B

Answer:

Solving for x (rearranging) you get:

(x^3+x+(x^2+1)^1/2)/x^2+1=y

Step-by-step explanation:

Solve for x by simplifying both sides of the equation and solving for y by isolating y