(b) The train is 61 cm long and travels at a speed of 18 cm/s.
It takes 4 seconds for the whole of the train to cross a bridge.
Calculate the length of the bridge.​

Answer:

Here for the comments .

Step-by-step explanation:

Answer:

The first Answer:

Step-by-step explanation:

The x-values are not the same on one line:

Image

The line connecting isn't perfect but see what I mean?

Answer:

The correct option is;

f(x) = -2·x² + 5·x - 1

Step-by-step explanation:

Given the points

(-1, -8), (0, -1), (1, 2), we have;

The general quadratic function;

f(x) = a·x² + b·x + c

From the given points, when x = -1, y = -8, which gives

-8 = a·(-1)² + b·(-1) + c = a - b + c

-8 =  a - b + c.....................................(1)

When x = 0, y = -1, which gives;

-1 = a·0² + b·0 + c = c

c = -1.....................................................(2)

When x = 1, y = 2, which gives;

2 = a·1² + b·1 + c = a + b + c...............(3)

Adding equation (1) to (3), gives;

-8 + 2 = a - b + c + a + b + c

-6 = 2·a + 2·c

From equation (2), c = -1, therefore;

-6 = 2·a + 2×(-1)

-2·a  = 2×(-1)+6 = -2 + 6 = 4

-2·a = 4

a = 4/-2 = -2

a = -2

From equation (1), we have;

-8 =  a - b + c = -2 - b - 1 = -3 - b

-8 + 3 = -b

-5 = -b

b = 5

The equation is therefore;

f(x) = -2·x² + 5·x - 1

The correct option is f(x) = -2·x² + 5·x - 1.

Hey there! I'm happy to help!

Since we are using graphs, we will do not need to algebraically solve this system of equations.

When you graph a system of equations, the solution is always the point at which the two lines intersect.

Here is our system of equations graphed. We see that the lines intersect at about (1 1/3, 2 1/3). Therefore, the correct answer is C. x=1 1/3, y=2 1/3

Have a wonderful day! :D

Answer:

charge = 18796 * 0.09$

=1691.64$

Step-by-step explanation:

Answer:

18796 * 0.09$

=1691.64$  

Step-by-step explanation:

Answer:

$29.25

Step-by-step explanation:

For every 1 hour, Carey earns $9.75.  Multiply $9.75 by 3 to find out how much she earns for 3 hours of work.

$9.75 × 3 = $29.25

Carey earns $29.25 for working 3 hours.

Answer:

29.25

Step-by-step explanation:

I got it right on edge!! trust me

Answer:

x = 10

Step-by-step explanation:

Since B is the midpoint of AC then AB = BC = 3x - 4 and

AB + BC = AC , thus

3x - 4 + 3x - 4 = 52, that is

6x - 8 = 52 ( add 8 to both sides )

6x = 60 ( divide both sides by 6 )

x = 10

Answer:

Step-by-step explanation:

perimeter of first square = 4 × side = 60 m

∴ side = 60/4 = 15 m

so area = s × s = 15 × 15 = 225 m^2

perimeter of second square = 4 × side = 144 m

∴ side = 144/4 = 36 m

so area = s × s = 36 × 36 = 1296 m^2

Perimeter of the third square = sum of areas of the first and second triangle

= 225 + 1296

= 1521 m

hope this helps

plz mark as brainliest!!!!!

Answer:

Perimeter of new square =  156 m

Step-by-step explanation:

First square:

 Perimeter = 60 m

 4 * side = 60 m

side = 60/4

side = 15 m

Area of first square = side * side = 15 * 15 = 225 m²

Second square:

 Perimeter = 144 m

 4 * side = 144 m

side = 144/4

side = 36 m

Area of second square = side * side = 36 * 36 = 1296 m²

New square:

Area of new square = area of first square + area of second square

                                  = 225 + 129

Area of new square = 1521 m²

   side * side = 1521

    side = √1521 = √39*39

     side = 39 m

Perimeter of new square = 4 * 39 = 156 m

Answer:

58

Step-by-step explanation:

Hello, let's note the two digits a and b. the first number 'ab' can be written as 10a +b. For instance if this is 24 it can be written 20 + 4.

If the digits are interchanged the number become 'ba' so 10b + a

We can say that 10a + b + 10b + a = 143

11(a+b)=143

We divide by 13 both sides and we take

a+b = 143/11 = 13

and we know that the digits differ by 3 so b = a + 3

then a + b = a + 3 + a = 2a + 3 = 13

so 2a = 10 and then a = 5

Finally, b = 5+3=8 so the number is 58.

And we can verify that 58 + 85 = 143.

Thanks

Answer:

❍ According to Question now,

➥ 10(x + 3) + x + 10x + x + 3 = 143

➥ 10x + 30 + 12x + 3 = 143

➥ 22x + 33 = 143

➥ 22x = 143 - 33

➥ 22x = 110

➥ x = 110/22

➥ x = 5

Therefore,

The unit digit number = x = 5

The tens digit number = x + 3 = 5 + 3 = 8

The original number = 10(x + 3) + x

The original number = 10(5 + 3) + 5

The original number = 50 + 30 + 5

The original number = 85

Hence,the original number is 85.

Answer:

[tex]\frac{(^3_1)*(^{37}_4)}{(^{40}_5)}[/tex]

Step-by-step explanation:

The total number of ways in which 5 specimens can be selected from the  dish at random is given as C(40, 5).

Since only one of the five specimens would have the trait, the number of ways of selecting the one specimen out of the 3 specimens with the trait is C(3, 1).

3 specimens have the trait therefore 37 specimens (40 - 3) do not have the trait. The number of ways in which the remaining 4 specimens out of the 5 spemimens that do not have the trait is C(37, 4).

Therefore, the probability that only 1 of the 5 specimens selected will have the trait = [tex]\frac{C(3,1)*C(37,4)}{C(40,5)} =\frac{(^3_1)*(^{37}_4)}{(^{40}_5)}[/tex]

Answer:

Step-by-step explanation:

An example of a negative correlation is tv viewing and student test grades.

Another example is the video game playing and test grades

Answer:

A. 2.24

Step-by-step explanation:

Multiply 56 by 0.04

56(0.04)

= 2.24

Answer:

Option A

Step-by-step explanation:

4% * 56 =

0.04 * 56 = (Convert the percent into a decimal.)

2.24 (Multiply)

Hope this helps.

Answer:

2x+59.

Step-by-step explanation:

Let J represent Jessica's weight and R represent Ronda's weight.

Jessica weighs x+34 pounds. Thus:

[tex]J=x+34[/tex]

Ronda weighs 12 pounds less than Jessica. In other words:

[tex]R=J-12=(x+34)-12\\R=x+22[/tex]

The sum of their weights, therefore, is:

[tex]J+R\\=(x+34)+(x+22)=2x+56[/tex]

Now, if Jessica gains 5 pounds and Ronda loses 2 pounds, the net gain of the total weight would be 3 pounds. Thus, we only need to add 3 to the original total to find the sum of their new weights:

[tex]2x+56+3=2x+59[/tex]

The sum of the new [weights] is represented by 2x+59.

Answer:

[tex]\huge\boxed{x = 8}[/tex]

Step-by-step explanation:

[tex]\sf -18 = -3x+6\\Subtracting \ 6 \ to \ both \ sides\\-18-6 = -3x\\-24 = -3x\\Dividing \ both \ sides \ by \ -3\\8 = x\\OR\\x = 8[/tex]

Answer:

x = 8

Step-by-step explanation:

Here, -3x = -24

x = 8

hope that helps you

Answer:

the new ratio milk/water is  14:6  or 7:3

Step-by-step explanation:

milk/water=5/3

milk +water=5+3=8

ratio of milk=5/8  and ratio of water=3/8

if 4 liter removed from mixture then: 20=4= 16 liter

the amount of milk in 16 liter=16*5/8=10 liter of milk

the amount of water in 16 liter=16*3/8= 6 liter

add 4 liter of milk to the mixture: 10+4=14 liter of milk and 6 liter of water

the new ratio milk/water is  14:6  or 7:3

Answer:

perpendicular means

m1 = 1/4

m2= -1/(1/4)

= -4 (Perpendicular slope)

(-6,-9) = (x1,y1)

so,

y-y1 = m (x-x1)

y-(-9)= -4 (x-(-6))

y+6 = -4 (x+6)

y+6 = -4x-24

y= -4x-24+6

y= -4x-18

hope it helps ^°^

Answer:

[tex]\displaystyle \boxed{y = -4x - 33}[/tex]

Step-by-step explanation:

[tex]\displaystyle y = \frac{1}{4}x[/tex]**

Now, perpendicular equations have OPPOSITE MULTIPLICATIVE INVERSE RATE OF CHANGES [SLOPES], so [tex]\displaystyle \frac{1}{4}[/tex]becomes −4 and you do the following:

−9 = −4[−6] + b

24

[tex]\displaystyle -33 = b \\ \\ y = -4x - 33[/tex]

I am joyous to assist you at any time.

Answer:

Area= 108ft²

Step-by-step explanation:

To find the area of a rectangle, you must do the following formula:

Area= Length × Width

A represents Area

L represents Length

W represents Width

Because the length (length is always longer than width) is 12 ft and the width (width is always shorter than length) is 9 ft. Your equation should be:

A= L × W

= 12ft × 9ft

= 108 ft²

Remember: The answer to a question asking for the area of a shape that is 2D, is always squared (let x represents the answer: x²). And the question asking the area of a shape that is 3D always cubed (let x represents the answer: x³). Always write the unit of measurement (let x represent the answer and cm as the example of unit of measurement: x cm²)

I hope this helps! I'm sorry if it's too complicated.

Answer:

G

Step-by-step explanation:

let his fixed price be x and his hourly fee be y;

270 = 4y + x

420 = 7y + x

x is common in both equations

equate the two;

x = 270-4y and x = 420-7y

270-4y = 420-7y

3y = 150

y = 50

x = 270-4*50

x = 70

Answer:

0.88175960442

Step-by-step explanation:

The square root of 0.7775 is 0.88175960442

The value of standard deviation will be;

⇒ 0.8803

What is mean by square root of a number?

A square root of a number is a value that multiplied by itself gives the same number.

Given that;

The value of Variance = 0.7775

Now,

Since, The standard deviation is the square root of the variance.

Hence, We can formulate;

The value of standard deviation = √0.7775

                                                 = 0.8803

Thus, The value of standard deviation will be;

⇒ 0.8803

Learn more about the standard deviation visit:

https://brainly.com/question/475676

#SPJ2

Answer:Conversion units

Step-by-step explanation: 1 ft^3= 0.028m^3 .: 1440ft^3=40.776m^3, so $1.75x40.776=$71.358~ $71.36.:

Answer:

$71.36

Step-by-step explanation:

1 foot = 0.3048 metros

1 cubic feet = (0.3048metros)³ = 0.02932 cubic meters   (aprox.)

1440 cubic feet = 1440*0.02932 = 40.7763 m

$1.75 por cubic meter:

1.75*40.7763 = $71.36

Answer:

4 is tenths (a) and 5 is hundredths (b)

Step-by-step explanation:

Now, 0.45

0 indicates the ones place (it comes before the decimal)

0.45 can also be written as:

0.4+0.05

= 4/10+5/100

what can we conclude from this?

we can say that 4 is in the tenths whilst 5 is in the hundredths.

therefore, a is 4 and b is 5.

Hope this helps you! :)

Answer:

     x = [tex]\frac{8}{9}[/tex]

Step-by-step explanation:

5x + 2 (x - 3) = -2 (x - 1)

  5x + 2x - 6 = -2x +2

5x + 2x + 2x = 2 + 6

               9x = 8

                 x = [tex]\frac{8}{9}[/tex]

Answer:

The value of x in the given equation is 0.89

Step-by-step explanation:

5x + 2(x - 3) = -2(x - 1)

Distribute 2 to (x - 3)

5x + 2x - 6 = -2(x - 1)

Distribute 2 to (x - 1)

5x + 2x - 6 = -2x + 2

Combine 5x and 2x on the left side of the equation.

7x - 6 = -2x + 2

Add 6 on both side of the equation.

7x = -2x + 8

Add 2x on both sides of the equation.

9x = 8

Now divide 9 from 8. Make sure you round the decimal because the quotient of these numbers is a repeating decimal.

x = 0.89

So, the value of x is 0.89

Answer:

The answer is -0.04

Step-by-step explanation:

Answer:

818.8333333 *pi

or

Using the pi button on the calculator

2572.440785

Using 3.14 for pi

2571.13666666

Step-by-step explanation:

We need the radius

r = d/2

r = 17/2 = 8.5

We can find the volume using

V = 4/3 pi r^3

V = 4/3 pi ( 8.5)^3

V =818.8333333 *pi

  Using the pi button on the calculator

2572.440785

Using 3.14 for pi

2571.13666666

Answer:

112°

Step-by-step explanation:

Arc CD is part of arc BCD, which is intercepted by the inscribed angle A.

Based on the inscribed angle theorem on circle, the sum of arc CD and CB is twice the measure of angle A.

That is:

CD + CB = 2(129°)

CD + 146 = 2*129

CD + 146 = 258

Subtract 146 from both sides to find CD

CD + 146 - 146 = 258 - 146

CD = 112°

Answer:

A

Step-by-step explanation:

Hi!

An exponent is the same thing as just multiplying the expression by itself the number of times the exponent says. So we need to multiply 1/3 by itself three times.

1/3 * 1/3 * 1/3 = 1/27

Answer:

\frac{\left(5x+1\right)\left(3x+1\right)}{2x-y}

Step-by-step explanation:

15x^2+8x+1:\quad \left(5x+1\right)\left(3x+1\right)

add on 2x -y as the denominator of the fraction

Answer:

1) x²+4x=2700

2) 50x50

Step-by-step explanation:

Pony area = x²

line-up area=4x

x²+4x=2700

x²+4x-2700=0

(x-50)(x+54)

So x= 50 or -54.  Since it can’t be a negative number, it must be 50.

CHECK:

Square = 50x50 = 2500

Line up area = 50x4 = 200

2500+200=2700 YES

The slope is the change in Y over the change in x:

Slope = (0-1) / 4-0) = -1/4

Slope = -1/4

Y intercept is the Y value when x is equal to 0. In the point (0,1) x is 0 and y is 1, so the y-intercept is 1

Answer:

The way a proportion is set is as follows;

[tex]\dfrac{1 \ inch}{200 \ miles } = \dfrac{4 \ inches}{ Distance \ from \ Rio \ de \ Janeiro \ to \ San \ Jose}[/tex]

The Distance from Rio de Janeiro and San Jose Costa Rica is then found as  800 miles

Step-by-step explanation:

The dimension of the distance between Rio de Janeiro and San Jose Costa Rica = 4 inches

The map scale = 1 inch to 200 miles

To figure out how many miles it is or the actual distance from Rio de Janeiro and San Jose Costa Rica, we have;

[tex]\dfrac{1 \ inch}{200 \ miles } = \dfrac{4 \ inches}{ Distance \ from \ Rio \ de \ Janeiro \ to \ San \ Jose}[/tex]

Therefore, we have;

(4 inches × 200 miles)/(1 inche) = Distance from Rio de Janeiro and San Jose Costa Rica

Which gives;

Distance from Rio de Janeiro and San Jose Costa Rica = 800 miles.