Please help quickly

Answer:

The speed of the boat in calm water is 12.8 miles per hour.

Step-by-step explanation:

While going downstream the speed of the boat is "x + 2", where x is the speed in calm water, while going upstream the speed of the boat is "x - 2". He made a trip that had two legs, each with a distance of 50 miles, therefore, the sum of the times it took him to complete each leg must be equal to the total time of the trip.

[tex]speed = \frac{distance}{time}\\\\time = \frac{distance}{speed}[/tex]

For the upstream:

[tex]time_{up} = \frac{50}{x - 2}[/tex]

For the downstream:

[tex]time_{d} = \frac{50}{x + 2}[/tex]

The sum of each of these times must be equal to "8 h", therefore:

[tex]8 = time_{up} + time_{d}\\\\8 = \frac{50}{x - 2} + \frac{50}{x + 2}\\\\8 = \frac{50*(x+2) + 50*(x - 2)}{(x-2)*(x+2)}\\\\8*(x-2)*(x+2) = 50*x + 100 + 50*x - 100\\\\8*(x^2 - 4) = 100*x\\\\8*x^2 - 100*x - 32 = 0\\\\x^2 - 12.5*x - 4 = 0\\\\x_{1,2} = \frac{-(-12.5) \pm \sqrt{(-12.5)^2 - 4*(1)*(-4)}}{2}\\\\x_{1,2} = \frac{12.5 \pm \sqrt{156.25 + 16}}{2}\\\\x_{1,2} = \frac{12.5 \pm \sqrt{172.25}}{2}\\\\x_{1,2} = \frac{12.5 \pm 13.124}{2}\\\\x_1 = 12.812\\\\x_2 = -0.312[/tex]

Since the speed can't be negative in this context, the only possible answer is 12.812 mph.

Answer:

12.8

Step-by-step explanation:

Answer:

b = 68

Step-by-step explanation:

Complementary angles add to 90 degrees

a+b = 90

22+b = 90

Subtract 22 from each side

b = 90-22

b = 68

Answer:

68 degrees

Step-by-step explanation:

Complementary Angles: The sum of the angles is 90 degrees.

If angle a is 22 degrees, then...

a + b = 90

22 + b = 90

22 - 22 + b = 90 - 22

b = 68

That means that the measure of angle b is 68 degrees.

I hope this helps! Have a great day!

A graph has a constant rate of change when the graph is linear and portrays a straight line. The slope will remain constant which forms the straight line in the graph.

Answer:

Because it is a straight line

Step-by-step explanation:

If it changed there would be curves, points, corners, zig zags, since this is straight, that means the R.O.C commonly known as slope, is not changing

I hope this helps u!

Pls give brainliest i had 40 down to 1 for no reason and a thx ;)

I always thank those who give me brainliest via their profile and comments

Answer:

C

Step-by-step explanation:

[tex]\frac{y^{3/4} }{y^{1/2} }[/tex]   Original expression

[tex]y^{\frac{3}{4}-\frac{1}{2} }[/tex]   Division Property of Exponents

[tex]y^{\frac{3}{4}-\frac{2}{4} }[/tex]   Find a common denominator (4)

[tex]y^{\frac{1}{4} }[/tex]   Simplify

[tex]\sqrt[4]{y}[/tex]   Rewrite as a radical expression (an exponent of 1/4 is equivalent to the 4th root of the expression)

Answer:

b<58/5

Step-by-step explanation:

I don't know, sorry. :(

Answer:

23/34

Step-by-step explanation:

This is guessing you only have fiction books.

Step-by-step explanation:

-12 +7

=-5 .

Therefore, 5-19-5

= -19.

In all, -12+7 can not be 5-19 or 19

Answer:

4. [tex]11.333...[/tex]

Answer:

Answer is  (4) -11.333

Step-by-step explanation:

multiply : 2x /12-4/3= 4x /15 -1/5

bring variable on one side :

2x/12 -4x/15= 4/3 - 1/5

common denominator : -6x/60=17/15

simplify : -x/10= 17/15

x= - 170/15= -11.3333

Answer:

242 integers

Step-by-step explanation:

We have to find the number of integers between 17 and 2678 which are the multiple of 11.

Divide 17 by 11 = [tex]\frac{17}{11}=1.55[/tex]

Smallest multiple of 11 which is greater than 11 = 2nd multiple = 22

Divide the largest number 2678 by 11 = [tex]\frac{2678}{11}=243.45[/tex]

Largest multiple of 11 which is less than 2678 = 443rd multiple

                                                                            = 243 × 11

                                                                            = 2673

Therefore, number of integers between 17 and 2678 multiple of 11

= 243 - 2 + 1

= 242 integers

Answer:

x= 9

Step-by-step explanation:

(3x + 4) and 50 are complementary angle

=> (3x + 4) + 50 = 90

-> 3x+4 = 40

-> 3x = 36

-> x= 9

The right answer is -14

please see the attached picture for full solution

Hope it helps

Answer:

2968

Step-by-step explanation:

First make 112% into a decimal, now its 1.12, add all the scooters' sales from all years and multiply by 1.12 then add that number to the total sales of the scooters

Answer:

725 + 579 + 696 = 2000 (What a coincidence)

112% = 112 / 100 = 1.12

Multiply the increase

2000 x 1.12 = 2240

2240 is the amount of scooters sold.

Step-by-step explanation:

Answer:

f(2) = -6

Step-by-step explanation:

f(x) = 3x - 12

Let x =2

f(2) = 3*2 -12

     = 6-12

       = -6

Answer: C

Step-by-step explanation:

Answer:

SA =64 pi units ^2

Step-by-step explanation:

The surface area of a sphere is given by

SA = 4 pi r^2

SA = 4 * pi * 4^2

SA =64 pi

SA =200.96

Answer:   [tex]\bold{a)\ \overline{CD}=6\qquad b)\ \overline{AD}=\dfrac{32}{3}\qquad c)\ \overline{AC}=\dfrac{50}{3}\qquad d)\ \overline{OB}=\dfrac{25}{3}}[/tex]

Step-by-step explanation:

a) First, use the Pythagorean Theorem to find CD:

8² + (CD)² = 10²     →     CD = 6

d) Next, find OB.  Notice that both OB and OC are the radius of the circle.

Using the Segment Addition postulate, we know the radius (r) = CD + DO  →  DO = r - 6

Use the Pythagorean Theorem for ΔOBD to find OB:

(DO)² + (BD)² = (OB)²

(r - 6)² + 8² = r²

r² - 12r + 36 + 64 = r²

   -12r + 100        = 0

             100        = 12r

              [tex]\dfrac{25}{3}\quad = r[/tex]              

c) Now, find AC. Notice that AC is the diameter.

Diameter = 2r

               = 2(OB)

               [tex]=2\bigg(\dfrac{25}{3}\bigg)\qquad =\dfrac{50}{3}[/tex]  

b) Lastly, find AD. Using the Segment Addition Postulate, we know that

AD + CD = AC   →   AD = AC - CD

                                      [tex]= \dfrac{50}{3}-6\qquad \rightarrow \quad \dfrac{50}{3}-\dfrac{18}{3}\qquad =\dfrac{32}{3}[/tex]

Answer: On a coordinate plane, a parabola opens up. It goes through (negative 3, 5), has a vertex at (negative 1.5, 2.75), and goes through (0, 5).

Step-by-step explanation: this is the one with a negative discriminant value

Answer:

iTS BBBB

Step-by-step explanation:

Just did it.

Answer:

Coordinates of M = [tex]\left ( -2,4 \right )[/tex]

Step-by-step explanation:

Given: AM:MB = 1:4, A has coordinates (-4, 3) and B has coordinates (6, 8)

To find: coordinates of M

Solution:

According to section formula, if M(x, y) divides line joining points [tex]A(x_1,y_1)\,,\,B(x_2,y_2)[/tex] in ratio [tex]m:n[/tex] then coordinates of point M are [tex]\left ( \frac{mx_2+nx_1}{m+n},\frac{my_2+ny_1}{m+n} \right )[/tex]

Put [tex]A(x_1,y_1)=(-4,3)\,,\,B(x_2,y_2)=(6,8)\,,\,m:n=1:4[/tex]

Therefore,

[tex](x,y)=\left ( \frac{6-16}{1+4},\frac{8+12}{1+4} \right )=\left ( -2,4 \right )[/tex]

Answer:

x = 1.6

Step-by-step explanation:

4x + 6x - 6 = 10

10x - 6 = 10

      +6    +6

      10x = 16

      10x/10 = 16/10

           x = 1.6

Answer:

5x^4+14x^2+1

Step-by-step explanation:

Hope that helps

Answer:

Proved;

See Explanation

Step-by-step explanation:

Given:

Shape: Parallelogram

Sides: b and c

Required:

Show that P = 2b + 2c

Let P represents the perimeter of the parallelogram.

There are 4 sides in a parallelogram where 2 sides are opposite and parallel

Given that two of the side of the parallelogram is b and c; this implies that the next two sides are also b and c.

This means that the sides of the parallogram are b,c,b,c

The perimeter of any shape is calculated by adding the lengths of the shape;

This means that

[tex]P = b + c + b + c[/tex]

Collect like terms

[tex]P = b + b + c + c[/tex]

[tex]P = 2b + 2c[/tex] ------ Proved

Answer:

Bottom left

Step-by-step explanation:

For it to be scalene, all 3 sides must be of different length, so cross off D. Acute means all angles are less then 90°, so cross off the top 2.

Answer: -105

Step-by-step explanation:

21 times -5 will be -105

Answer:

the one with 47:is 43

the one with 52 is 38

the one with 63 is 27

and the one with 45 is 45

Step-by-step explanation:

these angles equal to 90

so you must subtract them from 90

Answer:

5: x=43

6: x=38

7: x=27

8: x=45

Answer:

D

Step-by-step explanation:

Because the angle with measure 82 and angle 1 are corresponding angles, their angles measure must be equal, and therefore angle 1 has measure of 82 as well. Since angles 1 and 2 are a linear pair, they must be supplementary, and angle 2 is therefore 180-82=98 degrees. Hope this helps!

[tex]answer = 98 °\\ solution \\ < 1 = 82(being \: corresponding \: angless) \\ < 1 + < 2 = 180(sum \: of \: angle \: in \: straight \: line) \\ or \: 82 + < 2 = 180 \\ or < 2 = 180 - 82 \\ < 2 = 98° \\ hope \: it \: helps \\ good \: luck \: on \: your \: assignment[/tex]

Answer:

First Part is C

The second part is 0,2,4

Step-by-step explanation:

Edge said so

The graph of the solution is option (C) [tex]x\geq -3[/tex] is the correct answer.

An inequality is a relation which makes a non-equal comparison between two numbers or other mathematical expressions. It is the condition of being unequal. It is used most often to compare two numbers on the number line by their size.

For the given situation,

The expression is [tex]-3x-3\leq 6[/tex].

The graph below shows the inequality of the expression.

The solution of the expression is

[tex]-3x-3\leq 6[/tex]

⇒ [tex]-3x\leq 6+3[/tex]

⇒ [tex]-3x\leq 9[/tex]

Divide both sides by -3. Then the inequality will also get changed.

⇒ [tex]\frac{-3}{-3}x\geq \frac{9}{-3}[/tex]

⇒ [tex]x\geq -3[/tex]

Hence we can conclude that the graph of the solution is option (C) [tex]x\geq -3[/tex] is the correct answer.

Learn more about inequalities here

https://brainly.com/question/20383699

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Answer:

48

Step-by-step explanation:

Total points = 60

% = 80%

Therefore no. of points right = 80/100×60 = 48