It takes a boat 2 hours to go 16 miles downstream with the current and 4 hours to return against the current. Find the speed of the boat in still water and the speed of the current.

Answer:

a) x = 12  y = 9

b) x = -2   y = -4

c) x = 6   y = -2

Step-by-step explanation:

a)

Equation 1:  6x - 7y = 9

Equation 2:  3x + 2y = 54

Multiply Equation 2 by 2:

⇒ 6x + 4y = 108

Subtract equations:

   6x + 4y = 108

-    6x - 7y = 9      

           11y = 99

Divide both sides by 11:

⇒ y = 9

Substitute found value of y into Equation 1 and solve for x:

⇒ 6x - 7(9) = 9

⇒ 6x - 63 = 9

⇒ 6x = 72

⇒ x = 12

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b)

Equation 1:  4x - 5y = 12

Equation 2:  2x - 3y = 8

Multiply Equation 2 by 2:

⇒ 4x - 6y = 16

Subtract equations:

   4x - 6y = 16

-   4x - 5y = 12      

           -y = 4

Divide both sides by -1:

⇒ y = -4

Substitute found value of y into Equation 1 and solve for x:

⇒ 4x - 5(-4) = 12

⇒ 4x + 20 = 12

⇒ 4x = -8

⇒ x = -2

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c)

Equation 1:  4x - 2y = 28

Equation 2:  3x + 3y = 12

Multiply Equation 1 by 3:

⇒ 12x - 6y = 84

Multiply Equation 2 by 4:

⇒ 12x + 12y = 48

Subtract equations:

     12x - 6y = 84

-   12x + 12y = 48  

            -18y = 36

Divide both sides by -18:

⇒ y = -2

Substitute found value of y into Equation 1 and solve for x:

⇒ 4x - 2(-2) = 28

⇒ 4x + 4 = 28

⇒ 4x = 24

⇒ x = 6

Answer:

There are 2 options:

Step-by-step explanation:

That's a rectangular piece, therefore let's consider the width to be x and the length to be y.

A = width * length

1) A = x * y = 1,984 cm^2

P = 2 * (width) + 2 * (length)

2) P = 2x + 2y = 188 cm

Isolate x or y in one of the equations.

xy = 1,984 cm^2

y = 1,984 cm^2 / x

Now plug it in the second equation.

2x + 2y = 188 cm

2x + 2 * (1,984 / x) = 188

Now we have only one variable. Now just solve it alegebraically.

2x + (3,968 / x) = 188

Multiply both sides by x in order to get rid of the fraction.

[tex]2x^{2}[/tex] + 3968 = 188 x

Substract both sides by 188 x

2x^2 + 3968 - 188x = 0

Now divide by 2 to make the equation simpler.

x^2 - 94x + 1984 = 0

use the quadratic formula:

[tex]\frac{94 + \sqrt{(-94)^2 - 4(1)(1984)} }{2(1)} = 62\\\frac{94 - \sqrt{(-94)^2 - 4(1)(1984)} }{2(1)} = 32[/tex]    

  [tex]x1 = \frac{-b + \sqrt{b^2 - 4ac} }{2a} \\x2 = \frac{-b - \sqrt{b^2 - 4ac} }{2a}[/tex]

x is either 62 or 32.

let's find y:

y = 1,984 / x

y = 1,984 / 62 = 32

y = 1,984 / 32 = 62

There are 2 options:

Check the picture below.

a)

notice, since lines KP and NL are parallel, they make up the same angle in purple when they hit line MK, and both triangles share the green angle at M.

b)

notice, LP = LK = 14, and in an isosceles twin sides stemming from a vertex make twin angles.

Answer:

Scale (and/or) Scale Factor = 91.44

Step-by-step explanation:

First convert 15ft to cm

15ft = 457.2cm

Now divide the real whale size by the drawing

457.2 / 5 = 91.44

So the scale is 91.44

The whale is 91.44 times bigger than the drawing

Answer:

Asher should be 61

Step-by-step explanation:

Answer:

Here,

n(A)={0,1,3,5,6}

n(B)={1,2,3,7}

n(AUB)=?

we know that,

AUB={0,1,2,3,5,6,7}

Step-by-step explanation:

is it okay ?

hopefully it works <3 ❣️

Answer:

what is your question??????

Step-by-step explanation:

Answer:

0

Step-by-step explanation:

Answer:

Step-by-step explanation:

simply plug in the given values for the letter and do the math.

4(5) + 10 - 12 = 20+10-12 = 18.

Answer:

18

Step-by-step explanation:

w=12

x=10

y=5

z=9

4 (5)+10-12

20+10-12

BODMAS

addtition then subtraction

20+10=30

30-12

=18

Brainiest please

Answer:

48% chance to be female and 52% chance to be male.

Step-by-step explanation:

14 female + 15 males =  29 total people

a) 14 females/29 total = 0.48... * 100 = 48%

b) 15 males/29 total = 0.57.... * 100 = 52%

75 ÷ 15 = 5

the width is 5 inches

Answer:

Point [tex]A[/tex] is at [tex](-1/2,\, -2)[/tex].

Step-by-step explanation:

The intersection [tex](x,\, y)[/tex] of two lines in a plane could be found by solving a linear system of two unknowns ([tex]x[/tex] and [tex]y[/tex]) and two equations (one for each line.)

In this question, the equation of the two lines are [tex]y = 4\, x[/tex] and [tex]y = -2[/tex], respectively. The corresponding system of equations would be:

[tex]\left\lbrace \begin{aligned} & y = 4\, x \\ & y = -2\end{aligned} \right.[/tex].

Solve this system for [tex]x[/tex] and [tex]y[/tex]:

Therefore:

[tex]\left\lbrace \begin{aligned} & x = -\frac{1}{2} \\ & y = -2\end{aligned} \right.[/tex].

Thus, the coordinates of this intersection [tex](x,\, y)[/tex] would be [tex](-1/2,\, -2)[/tex].

Answer:

between 55 to 79 percent

Answer:

all shown in the picture !

Step-by-step explanation:

also shown in the picture

Answer:

778ft

Step-by-step explanation:

Answer:

Mean: 5.19 or 5.2

Median: 5

Range: 17

Step-by-step explanation:

Range: Q3 - Q1

0, 1, 1, 2, 2, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 7, 7, 7, 8, 8, 9, 9, 17

Here, we have 26 numbers

Minimum: 0

Maximum: 17

Median: 5 + 5 = 10/2 = 5

Lower quartile (Q1): 3

Upper quartile (Q3): 7

Range (biggest # - the smallest #): 17 - 0 = 17

Mean (add up all the numbers, and divide it by 26): 135/26 = 5.19 or 5.2

Hope this helps!

Answer:

25(m+3)

Step-by-step explanation:

25 is multiplied by (m+3)

'the sum of m and 3' is a quantity which must be indicated using parentheses

Hello!

The sum of means we add:

m+3

Multiply it times 25:

25(m+3)

The answer is Option C.

Now, the option you selected is wrong for the following reasons:

If you translate it into a verbal phrase, this is what it means:

25 plus the product of m and 3

Hence, Option C is correct.

Hope everything is clear.

Let me know if you have any questions!

Always remember: Knowledge is power! :-)

Answer:

9 or 9 months (if you have to add units)

Step-by-step explanation:

Subtract 15 from his savings:

420-15 = $405

This is the amount left he has to  pay the monthly membership

405/45 = 9

9 is the number of months

Answer:

9 months

Step-by-step explanation:

Set up and solve the equation 15 + 45x = 420.  Begin by subtracting 15 from both sides.  After paying 15 dollars for the deposit, He will have $405 dollars left.  Divide both sides of the equation by 45.  When you divide 405 by 45 that will tell you how many months the membership can be paid.

Answer:

2

Step-by-step explanation:

gradient =y² -y¹ /x²-x¹

=9-1/2--2

=8/4

=2

Answer:

y = 2x + 5

Step-by-step explanation:

There are 2 ways to find this equation:

The first way:  We have: y = ax + b (this is the line, right?)

The line is through the point (-2, 1) so we have:

1 = (-2)a + b      (1)

The line is also through the point (2, 9) so we have:

9 = 2a + b.       (2)

From (1) and (2) we get a equals 2, b equals 5. Then:
y = 2x + 5

The second way:

Let A(-2, 1) and B(2, 9), then AB = (4, 8).

=> The normal vector of this line is n = (-2, 1).

The line that is through the points A(-2, 1) and B(2, 9), and has the normal vector n=(-2, 1) has the equation:

[tex]-2(x - 2) + 1(y - 9) = 0[/tex]

[tex]-2x + y - 5 =0\\ < = > y = 2x + 5[/tex]

Answer:

∠B = 70 and ∠C = 40

Step-by-step explanation:

The image is not loading for me but with isosceles triangles there will two angles that are the same and one different angle.

All the angles will add up to equal 180 degrees.

In this case the different angle would angle C as the two same lines meet at that point.

From this you can that angle A and B are the same, both 70, so angle C would be:

180 (all the angles of a triangle added together) - 70 - 70 = 40

I'm assuming that x and y are angles B and C as they are not stated so they would be: ∠B = 70 and ∠C = 40.

Here is a diagram to demonstrate this:

Answer:

East

Step-by-step explanation:

Arkansas is East of Oklahoma.

Refer to the image below:

Answer: East

Step-by-step explanation:

Answer:

x=2.16

Step-by-step explanation:

1. Cross multiply.  3.5x(5) = 9(4.2)

2. Simplify. 17.5x=37.8

3. Divide both sides by 17.5. x=2.16

Answer:

[tex]\displaystyle [-2, 7][/tex]

Step-by-step explanation:

You want to eradicate one pair of variables so they are set to zero. It does not matter which pair is selected:

[tex]\displaystyle \left \{ {{4x + 2y = 6} \atop {-2x + 2y = 18}} \right.[/tex]

{½[4x + 2y = 6]

{−2x + 2y = 18

>> [tex]\displaystyle \left \{ {{2x + y = 3} \atop {-2x + 2y = 18}} \right. \\ \\ \frac{3y}{3} = \frac{21}{3} \\ \\ \\ y = 7[/tex]

Plug this back into the system to get the x-value of [tex]\displaystyle -2.[/tex]

I am joyous to assist you at any time.

Step-by-step explanation:

Question 2(Multiple Choice Worth 1 points)

(08.02 MC)

The function f(t) = 4t2 − 8t + 7 shows the height from the ground f(t), in meters, of a roller coaster car at different times t. Write f(t) in the vertex form a(x − h)2 + k, where a, h, and k are integers, and interpret the vertex of f(t).

f(t) = 4(t − 1)2 + 3; the minimum height of the roller coaster is 3 meters from the ground

f(t) = 4(t − 1)2 + 3; the minimum height of the roller coaster is 1 meter from the ground

f(t) = 4(t − 1)2 + 2; the minimum height of the roller coaster is 2 meters from the ground

f(t) = 4(t − 1)2 + 2; the minimum height of the roller coaster is 1 meter from the ground

When we add 82.545 and 128.580 we get a total of 211.125, now the closest number to the answer is B. 211.125Addition of Numbers

Given Data

Apart from addition of numbers there are other mathematical operations we can perform on integer numbers like in our example above

they are

Total Number = 82.545 + 128.580Total Number = 211.125

Learn more about Mathematical Operations of numbers here:https://brainly.com/question/10679598

Answer:

B

Step-by-step explanation:

Took the test, have a good day.

Answer:

9n + 2

Step-by-step explanation:

Answer:

[tex]9p+2[/tex]

Hope This Helps! Please give Brainliest!

Answer:

  acute, acute, obtuse*, right, obtuse

Step-by-step explanation:

The Pythagorean theorem is used as a reference for classifying triangles from their side lengths. If the sum of the squares of the short sides is equal to the square of the long side, then the triangle is a right triangle. If the long side is too short, then triangle is acute. If the long side is too long, the triangle is obtuse.

__

The math can be tedious, so it is convenient to let a spreadsheet do it. The results are attached.

The first two triangles are acute; the 4th one is a right triangle, and the remaining two are obtuse.

_____

Additional comment

* Note that triangle #3, with side lengths 2, 4, 6, is classified as "obtuse" because the largest angle is greater than 90°. In fact, with those side lengths, the largest angle is 180°. Some would argue it isn't a triangle at all because its area is 0 and it looks like a line segment.

(Our spreadsheet doesn't care if the triangle inequality is not satisifed. It is only concerned with the Pythagorean theorem.)

Take one side

Scale factor (A to B)

[tex]\\ \rm\rightarrowtail \dfrac{3}{9}=\dfrac{1}{3}[/tex]

#2

Scale factor Bto A:-

Scale factor (Ato B)=3/2

Answer:

The scale factor can either increase or decrease the size of an object. To find the scale factor of dilation:

[tex]\textsf{Scale factor} = \dfrac{\textsf{Dimension of the new shape}}{\textsf{Dimension of the original shape}}[/tex]

For these questions:

Question 1

[tex]\sf \implies scale \ factor=\dfrac{9}{3}=3[/tex]

Question 2

[tex]\sf \implies scale \ factor=\dfrac46=\dfrac23[/tex]

Answer:

Part A: 512 ft²

Part B: 3 cans

Step-by-step explanation:

Part A:

We can divide the shape into 2 areas or rectangles.

The top rectangle's area: 20 x 12 =240

The bottom: 34 x 8 = 272

add these 2 up, 240 +272, and you get 512, the area of this figure.

Part B:

We have to divide the number of feet covered by the area:

512/200 = 2.56

However, we half to round up, cause we cant buy part of a can, we have to buy a whole one.

So, we get 3 cans.