25 Points please help!!!

Answer:

n(E) = 6

Step-by-step explanation:

That's to say that there are 6 five-digit numbers with 7 in the first place and 8 in the last place, using the digits 2, 3, 4, 7 and 8. Therefore n(E) = 6.

Answer:

2x - 19 + x + 4

Step-by-step explanation:

2x - 19 + x + 4

Answer:

[tex]x=k\frac\pi2; k\in \mathbb{Z}[/tex]

Step-by-step explanation:

Let's use the formulas that change a sum of two sines into a product:

[tex]sin\ p + sin\ q =2 sin{\frac{p+q}2}cos{\frac{p-q}2}[/tex]

[tex]sin 3x+sinx =2sin \frac{3x+x}2 cos \frac{3x-x}2 = 2(sin2x)(cosx)=0[/tex]

At this point it's either [tex]sin 2x =0 \implies 2x= k\pi \rightarrow x = k\frac{\pi}2[/tex]

or [tex]cosx=0 \rightarrow x=\frac\pi2+ k\pi = (2k+1)\frac\pi2[/tex]

with the usual condition of [tex]k\in \mathbb{Z}[/tex].

Now if you look at both sets of solutions, first one considers all multiples of [tex]\frac\pi2[/tex], while the second only the odd multiples. it means that the first includes the second.

Answer:

After 5 minutes, it remains 75.73 grams of mass.

Step-by-step explanation:

Each minute, the mass is decreased by a 25.5%. So, we can find the mass after each minute period.

First minute.

330gr - 0.255 (330gr)= (330 - 84.15)gr = 245.85gr

Second minute.

245.85 - 0.255 (245.85) = 245.85 - 62.69 = 183.16gr

Third minute.

183.16 - 0.255 (183.16) = 183.16- 46.70= 136.45gr

Fourth minute.

136.45- 0.255 (183.16) - 136.45 - 34.80= 101.65gr

Fifth minute.

101.65 - 0.255 (101.65)= 101.65 - 25.92= 75.73gr

Therefore, after 5 minutes, it remains 75.73 grams of mass.

Answer:

2/7 or -30/7

Step-by-step explanation:

Use the quadratic formula

a = 7, b = 2, c = -1

-2 + or - (sqrt (2^2 - 4 * 7 * -1) / 2 * 7

-2 + or - 32/14

-2 + or -  16/7

2/7, or -30/7

Answer:

Step-by-step explanation:

7x² + 2x - 1 = 0

x = (-2 ±[tex]\sqrt{2^2 - 4(7)(-1)}[/tex] )/ (2(7))

x = (-2 ± [tex]\sqrt{32}[/tex] ) /14

x = (-2 ± 4[tex]\sqrt{2}[/tex] ) /14

x = [tex]\frac{-1}{7}[/tex] ± [tex]\frac{2}{7}[/tex][tex]\sqrt{2}[/tex]

Answer:

a- (1,1) (3,4) (9,7)

Hope you could get an idea from here.

Doubt clarification - use comment section.

Answer:

Step-by-step explanation:

You are after time. You know the total distance. They start off at the same time and meet after t hours

Let the meeting time = t

Let the distance from Mary's standpoint be d

Mary

d = r * t

r = 1 mile / hour

t = ?

Ava

d = r*t

d for Ava = 10 - d

r = 4 mile / hour

Solution

10 - d = 4 * t

The time is the same for both people

Ava: divide both sides by 4

10/4 - d/4 = t

Mary

d = 1 * t

d = t

10/4 - d/4 = d        Add d/4 to both sides.

10/4 = d + d/4

10/4 = 5d / 4        Multiply both sides by 4

10 = 5d                Divide both sides by 5

10/5 = 5d/5

d = 2

Since from Mary we have d = t

They will meet in 2 hours.

Given: JK = 3x - 5, KL = 2x + 1

The sum of the segments JK and KL will equal the length of the segment JL = 16

So we can write:

3x - 5 + (2x + 1) = 16 [JK + KL = JL]

Collect terms, solve for x:

5x - 4 = 16

5x = 20

x = 4

JK = 3x - 5 = 3*4 - 5 = 12 - 5 = 7

Ans: 7

Answer:

[tex]y = \frac{2}{3} x + 2[/tex]

Step-by-step explanation:

Start by finding the slope of the given line.

[tex]\boxed{ slope = \frac{y _{1} - y_2 }{x_1 - x_2} }[/tex]

Slope of given line

[tex] = \frac{5 - ( - 1)}{ - 2 - 2} [/tex]

[tex] = \frac{5 + 1}{ - 4} [/tex]

[tex] = \frac{6}{ - 4} [/tex]

[tex] = - \frac{3}{2} [/tex]

A perpendicular bisector cuts through the line at its midpoint perpendicularly.

The product of the slopes of two perpendicular lines is -1.

Let the slope of the perpendicular bisector be m.

[tex] - \frac{3}{2} m = - 1[/tex]

[tex]m = - 1 \div ( - \frac{3}{2} )[/tex]

[tex]m = - 1 \times ( - \frac{2}{3} )[/tex]

[tex]m = \frac{2}{3} [/tex]

[tex]y = \frac{2}{3}x + c[/tex], where c is the y-intercept.

To find the value of c, we need to substitute a pair of coordinates that lies on the perpendicular bisector into the equation. Since the perpendicular bisector passes through the midpoint of the given line, we can use the midpoint formula to find the coordinates.

[tex]\boxed{midpoint = ( \frac{x _{1} + x _2}{2} , \frac{y_1 + y_2}{2} )}[/tex]

Midpoint of given line

[tex] = ( \frac{ - 2+ 2}{2} , \frac{5 - 1}{2} )[/tex]

[tex] =( \frac{0}{2} , \frac{4}{2} )[/tex]

= (0, 2)

[tex]y = \frac{2}{3} x + c[/tex]

When x= 0, y= 2,

2= ⅔(0) +c

2= 0 +c

c= 2

Thus, the equation of the perpendicular bisector is [tex]y = \frac{2}{3} x + 2[/tex].

Answer: 26 = 4x + 10 and Cheryl goes running four times per week.

Step-by-step explanation: Let x equal the number of times Cheryl runs. 26 minus 10 is 16. 16 divided by 4 is 4.

Answer: For Y the rate of change is +4

For the rate of x its +5

Step-by-step explanation:

Answer:

[tex]259 \frac{21}{46}[/tex]

Step-by-step explanation:

In order to solve this question we will need to use BODMAS to help us get a reasonable answer. If you don't know what BODMAS is it stands for:

B: Brackets

O: Orders

D: Division

M: Multiplication

A: Addition

S: Subtraction

First Step:

1.  [tex]275/92*50[/tex]

First we multiply 50 by 275. Then we divide this result by 92.

[tex]275/92*50=6875/46[/tex]

Second Step:

2. [tex]45+45-45+45-45+65[/tex]

Now lets subract and minus and such that we get 110.

[tex]110[/tex]

Third Step:

Now we combine both these value and we get [tex]259 \frac{21}{46}[/tex]

Answer:

[tex]x=21[/tex]

Step-by-step explanation:

First of all, the two blue angles (i painted on the image) are congruent since opposed to the vertex.

At this point the red angle is a right angle while the green one is 180°. At this point it's a simple system of linear equations:

[tex]\left \{ {{3x+7+y=90} \atop {5y+10+3x+7=180}} \right. \\\left \{ {{3x+y=83} \atop {3x+5y=163}} \right. \\\\15x+5y-3x-5y=415-163 \rightarrow 12x=252 \rightarrow x=21[/tex]

Answer:

Step-by-step explanation:

First we need to find the 20% discount.

$32.99 x .20 = $6.598

The 20% discount is $6.59

We subtract the discount from the original price:

$32.99 - $6.59 = $26.40 (This is price after the discount.)

Now we need to find the amount of the sales tax on the discounted price.

$26.40 x .08 = $2.11 (This is the sales tax on the discounted price.)

The total price Andre paid is the discounted price plus the sales tax.

$26.40 + $2.11 = $28.51

Total price paid: $28.51

Answer: 1 1/3 miles

Step-by-step explanation:

Since we know that an hour is 60 minutes, and 60 divided by 15 = 4, then we can multiply 1/3 times 4 to get the total number of miles in 60 minutes.

1/3 X 4 = 4/3

4/3 = 1 1/3

Therefore, the answer is 1 1/3 miles.

Therefore, in an hour, a person will walk 4/3 mile.

Hoped this helped.

[tex]BrainiacUser1357[/tex]

Answer:

D. Energy.

Step-by-step explanation:

Liquid is at a higher energy state than a solid.

When the liquid turns into a solid, then the energy gets changed. Then the correct option is D.

When a liquid's temperature drops below its freezing point, a phase shift called freezing occurs, converting it from a liquid to a solid. According to the widely accepted definition, freezing refers to the liquid content of a substance changing from a liquid to a solid during a cooling process.

When a liquid's molecules slow down enough to attract one another into permanent positions as a solid, this process is known as freezing.

The term "single solidification point" refers to the temperature at which an alloy transitions from a completely liquid state to a fully solid state without traveling through a partially liquid state, meaning that no additional cooling is necessary to create a fully solid alloy.

The energy is altered as a liquid changes into a solid. D is the right answer in this case.

More about the solidification link is given below.

https://brainly.com/question/392491

#SPJ2

Answer:

64 square feet

Step-by-step explanation:

A = s² = 8² = 8*8 = 64

Answer: 4.5

Step-by-step explanation:

30% is equal to 30/100, which is 0.3

If you times 0.3 by 15, you will get 30% of 15

Therefore the answer would be 0.3 x 15 = 4.5

Answer:

y=7/3x

Step-by-step explanation:

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

m=(-7-0)/(-3-0)

m=-7/-3

m=7/3

y-y1=m(x-x1)

y-0=7/3(x-0)

y=7/3(x)

y=7/3x

Equation of the line through (0,0) and (-3,-7) is y=7/3x

The slope of the line is the ratio of the rise to the run, or rise divided by the run. It describes the steepness of line in the coordinate plane.

The slope intercept form of a line is y=mx+b, where m is slope and b is the y intercept.

The slope of line passing through two points (x₁, y₁) and (x₂, y₂) is

m=y₂-y₁/x₂-x₁

We need to find the equation of the line through (0,0) and (-3,-7)

m=-7/-3=7/3

Now let us find the y intercept

-7=7/3(-3)+b

b=0

So the equation is y=7/3x

Hence, equation of the line through (0,0) and (-3,-7) is y=7/3x

To learn more on slope of line click:

https://brainly.com/question/14511992

#SPJ5

Answer: betina or adelita

Step-by-step explanation: hope it helps

Answer:

Step-by-step explanation:

Arithmetic sequences have a common difference. Often, checking for that is the easiest. Geometric sequences have a common ratio. If there is neither a common difference nor a common ratio, then the sequence is not one of these types.

The difference or ratio refers to the relation of a term in the sequence to the one before it. For example, 94.1 -98.3 = -4.2. If the same difference exists for subsequent pairs of terms, then the difference is said to be "common." Likewise, 3.5/1.75 = 2. If the same ratio exists for subsequent pairs of terms, it is a "common" ratio.

__

98.3, 94.1, ... -- arithmetic (common difference = -4.2)

1, 0, -1, 0, ... -- neither

1.75, 3.5, ... -- geometric (common ratio = 2)

-12, -10.8, ... -- arithmetic (common difference = -1.2)

-1, 1, ... -- geometric (common ratio = -1)

Answer: Arithmetic (98.3,94.1, 89.9, 85.7,...)  (-12,-10.8, -9.6,-8.4)

Geometric (1.75,3.5,7, 14) (-1,1,-1,1,...)

Neither (1,0,-1,0,...)

Step-by-step explanation:

I guarantee these are correct.

Slope is the change in Y over the change in x.

Use 2 points on the graph(x,y) to use to solev6.

(2,3) and (0,-7)

Slope = (-7 -3) / (0-2)

Slope = -10/-2

Slope = 5

Answer: A the slope is 5

Answer:

Step-by-step explanation:

2 + 14 = 16 x 3 = 48

Answer: $11.48

Step-by-step explanation:

First of all, you have to multiply 3.25 by 2.55 because the grapes are 2.55 per pound. That makes 8.2875 for the first occasion. Next, you have to multiply 1.25 by 2.55 for the second occasion. That makes 3.1875. You then have to add 8.2875 and 3.1875. You get 11.47500, and that rounded to the nearest cent is $11.48.

Answer:

(9/7)^1

Step-by-step explanation:

(7/9)^-1

use rule a^-b = 1/a^b

som

1/(7/9)^1

(9/7)^1

Answer:

A-4.51

Step-by-step explanation:

I was going to ask to what place but then I saw all the others wouldn't make sense.