necesito ayuda con esto

Answer:

25.

Step-by-step explanation:

Let the number of pupils be x, then:

there are 0.6x girls and 0.4x boys.

From the given information:

0.6x - 0.4x = 5

0.2x = 5

x = 5/0.2

= 50/2

= 25.

Answer:

[tex]VR=5[/tex]

Step-by-step explanation:

From the question we are told that:

No of Pulleys =5

Generally Greatest VR is achieved if it has no friction to the pulleys

Therefore

[tex]W=5P[/tex]

Generally the equation for Efficiency  is mathematically given by

[tex]n=\frac{MA}{VR}[/tex]

Where

MA=mechanical advantage

Therefore  at Greatest VR

[tex]n=100 \%[/tex]

[tex]MA=VR[/tex]

[tex]VR=\frac{W}{P}[/tex]

[tex]\frac{W}{P}=5[/tex]

[tex]VR=5[/tex]

Answer:

20 degrees

Step-by-step explanation:

we can consider 33 to be the radius of a circle.

31 would then be the cos of the angle in that circle.

the regular cos function is defined for the standard circle with radius 1. so, that would be multiplied by 33 for this circle here.

31 = cos(?) × 33

cos(?) = 31/33 = 0.9393...

? = 20.05 ≈ 20 degrees

3x ² - 2x + 1 = 2x ² - 3x + 7

x ² + x - 6 = 0

(x + 3) (x - 2) = 0

x + 3 = 0   or   x - 2 = 0

x = -3   or   x = 2

Answer:

£ 157.5

Step-by-step explanation:

12.5  × 180 = 22.5

100

180 - 22.5 = 157.5

I hope this helps.

Answer:

\left(-32ux+19u^2x^3-12u^6x^7\right)\:divided\:by\:\left(-4u^2x^3\right)

Step-by-step explanation:

Factor the numerator and denominator and cancel the common factors.

\frac{8}{ux^2}\:-\frac{19}{4}+3u^4x^4

Answer:

Kristi will pay $22.77 for the shirt.

Step-by-step explanation:

First, determine the sales price of the shirt. If the full price is $27.99, a 25% reduction is $7. Subtract the discount from the full price to get a sales price of $20.99 for the shirt.

Next, determine the amount of tax Kristi will pay for the shirt. In her state, the sales tax is 8.5% (0.085). Multiply $20.99 by 0.085 and you will see that the sales tax is $1.78. Add the amount of the tax, $1.78, to the sales price of the shirt, $20.99, and you will get $22.77 as the cost of the shirt after the sales tax is added.

Answer:

See graph

[tex](x +3)^{2}[/tex] + [tex](y + 1)^{2}[/tex] = 9

(-3 , -1) is the center.

[tex]\sqrt{9}[/tex] = 3 = radius

Step-by-step explanation:

[tex](x - h)^{2} + (y - k)^{2} = r^{2}[/tex]

center (h,k)

radius = r

Answer:

B

Step-by-step explanation:

[tex]d \: = \frac{h}{24} [/tex]

make h the subject of the formula

h = 24 d

Answer:

the answer is as follows:

Step-by-step explanation:

a)

The equation has the following integer solutions:

5*x+25=-3*xy+8*y^2

Number of solutions found: 3

x1=-31; y1=-10

x2=-7; y2=-2

x3=-5; y3=-0

b)

The equation has the following integer solutions:

2*y^2+x+y+1=x^2+2*y^2+xy

Number of solutions found: 2

x1=0; y1=-1

x2=2; y2=-1

 Do not forget to give appriciation.

Answer:

Step-by-step explanation:

That was some horse.

20*t + 30*t = 800           Each day he rode the same amount of time (t). On the first day, he rode a distance of 20*t. On the second day, he rode a distance of 30*t

50t = 800

t = 800/50

t = 16

Each day he rode 16 hours

Total time = 32 hours.

Answer:

32 hours

Step-by-step explanation:

Step-by-step explanation:

First sentence

Let the number be X

second sentence

X-5

Third sentence

X-5=14

X=19

The number is 19

Hi there!  

»»————-　★　————-««

I believe your answer is:

19

»»————-　★　————-««  

Here’s why:  

⸻⸻⸻⸻

[tex]\text{"I am thinking of a number. l take away 5. The result is 14."}\\\\\text{5 taken away from 'said number' would be 14.}\\\\\boxed{n-5=14}\\\\\\\boxed{\text{Solving for 'n'...}} \\\\\rightarrow n - 5 + 5 = 14 + 5\\\\\rightarrow \boxed{n = 19}[/tex]

⸻⸻⸻⸻

»»————-　★　————-««  

Hope this helps you. I apologize if it’s incorrect.  

Answer:

63

Step-by-step explanation:

a=9

7a

7(9)

63

Answer:

(x-12)^2+(y-2)^2=4

Step-by-step explanation:

Answer:

Step-by-step explanation:

The answer is 4.

Once you add 4, you get:

x^2 -2x + 4 = 7.

The left side is factorable:

(x-2)^2 = 7.

There is your perfect square.

Answer:

1) The length of [tex]DC[/tex] is 20.

2) The length of [tex]PS[/tex] is 17.

Step-by-step explanation:

1) If [tex]DR = RE[/tex] and [tex]CS = SB[/tex], then we can use the following proportionality ratio:

[tex]\frac{DE}{DR} = \frac{32 - x}{26 - x}[/tex] (1)

Where [tex]x[/tex] is the length of segment [tex]\overline{CD}[/tex].

If [tex]DE = 2\cdot DR[/tex], then the value of [tex]x[/tex] is:

[tex]2 = \frac{32-x}{26-x}[/tex]

[tex]52 - 2\cdot x = 32 - x[/tex]

[tex]20 = x[/tex]

The length of [tex]DC[/tex] is 20.

2) If [tex]QV = VP[/tex] and [tex]RW = WS[/tex], then we can use the following proportionality ratio:

[tex]\frac{QP}{QV} = \frac{x-7}{12-7}[/tex] (2)

Where [tex]x[/tex] is the length of segment [tex]\overline{PS}[/tex].

If [tex]QP = 2\cdot QV[/tex], then the value of [tex]x[/tex] is:

[tex]2 = \frac{x-7}{5}[/tex]

[tex]10 = x-7[/tex]

[tex]x = 17[/tex]

The length of [tex]PS[/tex] is 17.

======================================================

Explanation:

The rule we use is

a^b * a^c = a^(b + c)

This says that if we multiply exponential expressions with the same base, then we add the exponents. We keep the base the same the entire time.

For example, 2^3*2^4 = 2^(3+4) = 2^7

--------------

For this problem, we'll say,

5^(56)*5^(22)*5^(-96)

5^( 56+22+(-96) )

5^(-18)

Be sure that you use parenthesis so that you tell your teacher that all of the -18 is in the exponent. Saying 5^-18 could lead to ambiguity.

Answer:

sorry it he question isn't clear

Answer,

C

Step-by-step explanation:

I had the same question 2 days ago

Answer:

BE.

Step-by-step explanation:

If AD is to DG, then BE must be to EH, and CF must be to FI.

Answer:

C

Step-by-step explanation:

y=-x^2+1. y is a decreasing function as x^2 is an increasing function

Answer:

Step-by-step explanation:

[tex]\sf \: {x}^{2} - 5[/tex]

[tex]\sf \: Use \: the \: algebraic \: identity \\ \sf \: a {}^{2} - {b}^{2} = (a - b)(a + b)[/tex]

[tex]\sf \: Substitute \: the \: value \: of \: a \: and \: b \: in \: the \: identity.[/tex]

[tex]\sf \: a = \sqrt{x ^{2} } = x \\ \sf \: b = \sqrt{5} [/tex]

[tex]\sf \: the \: identity \: becomes \: [/tex]

[tex]\sf {x}^{2} - 5 \\ \sf = (x - \sqrt{5} )(x + \sqrt{5} ) \\ [/tex]

Answer ⟶ [tex]\boxed{\bf{(x - \sqrt{5} )(x + \sqrt{5} )}}[/tex]

[tex] \huge \mathtt \blue{answer}[/tex]

Here, “p” is a numerator and “q” is a denominator. The examples of rational numbers are 6/5, 10/7, and so on. The rational number is represented using the letter “Q”. Like real numbers, the arithmetic operations, such as addition, subtraction, multiplication, and division are applicable to the rational numbers.

Answer:

[tex]x = 4[/tex]

Step-by-step explanation:

Step 1:  Solve for x

Since there are two parallel lines and one perpendicular line through the middle, that means that all of the angles are equal.  Therefore, we can make an equation 21x + 6 = 90 and solve for x

[tex]21x + 6 - 6 = 90 - 6[/tex]

[tex]21x / 21 = 84 / 21[/tex]

[tex]x = 4[/tex]

Answer:  [tex]x = 4[/tex]

Answer:

C is the answer 3rd one...

Answer:

next 3 terms are -15, -28, -41. The formula would be n= (n-1)-13 to get the nth term

Step-by-step explanation:

Answer:

Step-by-step explanation:

The rectangle has 4 corners of 90 degrees.

Here a rectangle is divided into two right triangles. In right-angled triangles, the opposite side at a 30-degree angle is half a chord...I replace x instead of length.. So x / 2 = 4--->x:8

The perimeter of a rectangle is equal to (length + width) × 2--->(8+4)×2=24m^2

Answer:

[tex]\text{(D) }16\sqrt{3}\:\mathrm{m^2}[/tex]

Step-by-step explanation:

In all 30-60-90 triangles, the sides are in ratio [tex]x:2x:x\sqrt{3}[/tex], where [tex]x[/tex] is the side opposite to the 30 degree angle and [tex]2x[/tex] is the hypotenuse of the triangle.

The rectangle shown forms two 30-60-90 triangles. The side labelled 4 meters is opposite to the 30 degree angle. Therefore, the side on top must be [tex]x\sqrt{3}\text{ for }x=4[/tex]. Let the length of the top base be [tex]w[/tex]:

[tex]w=4\sqrt{3}[/tex]

The area of a rectangle with length [tex]l[/tex] and width [tex]w[/tex] is given by [tex]A=lw[/tex]. Thus, the area of the rectangle is:

[tex]A=4\cdot 4\sqrt{3},\\A=\boxed{16\sqrt{3}\:\mathrm{m^2}}[/tex]