hlep me it is easy plssssssssssssss

Answer:

Step-by-step explanation:

The progression of sums is ...

  1, 5, 15, 34, 65, ...

So, first differences are ...

  4, 10, 19, 31

Second differences are ...

  6, 9, 12, ...

Third differences are constant:

  3, 3, ...

This means the expression for Sn will be a cubic expression. If dn is the first of the n-th differences, then the equation can be written as ...

  Sn = S1 +(n -1)(d1 +(n -2)/2(d2 +(n -3)/3(d3)))

And this simplifies a little bit to ...

  Sn = 1 +(n -1)(4 +(n -2)(n +3)/2)

In simpler form, we have ...

  Sn = 1/2(n³ +n)

Then the two terms we're interested in are ...

  S7 = (1/2)(7³ +7) = 175

  S17 = (1/2)(17³ +17) = 2465

Each term Sₙ consists of the sum of a triangular number of terms, which are given by

[tex]T_n = \displaystyle \sum_{k=1}^n k = 1 + 2 + 3 + \cdots + n = \frac{n(n+1)}2[/tex]

The triangular numbers are given recursively for n ≥ 1 by

[tex]T_n = T_{n-1} + n[/tex]

starting with T₀ = 0.

For example,

• S₁ = 1 and

[tex]\displaystyle S_1 = \sum_{k=T_0+1}^{T_1} k = \sum_{k=1}^1 k = 1[/tex]

• S₂ = 2 + 3 and

[tex]\displaystyle S_2 = \sum_{k=T_1+1}^{T_2} k = \sum_{k=2}^3 k = 2 + 3[/tex]

• S₃ = 4 + 5 + 6 and

[tex]\displaystyle S_3 = \sum_{k=T_2+1}^{T_3} k = \sum_{k=4}^6 k = 4 + 5 + 6[/tex]

Then the n-th term of the sequence we're considering is

[tex]S_n = \displaystyle \sum_{k=T_{n-1}+1}^{T_n} k = \sum_{k=T_{n-1}+1}^{T_{n-1}+n} k[/tex]

Expanding this sum, we have

[tex]S_n = \left(T_{n-1}+1\right) + \left(T_{n-1}+2\right) + \left(T_{n-1}+3\right) + \cdots + \left(T_{n-1}+n\right)[/tex]

There are n terms on the right side, and hence n copies of [tex]T_{n-1}[/tex], and the rest of the terms make up the next triangular number [tex]T_n[/tex] :

[tex]S_n = nT_{n-1} + 1 + 2 + 3 + \cdots + n[/tex]

[tex]S_n = nT_{n-1} + \displaystyle \sum_{k=1}^n k[/tex]

[tex]S_n = nT_{n-1} + T_n[/tex]

We have a closed form for [tex]T_n[/tex], so we end up with

[tex]S_n = n \cdot \dfrac{(n-1)n}2 + \dfrac{n(n+1)}2 \implies \boxed{S_n=\dfrac{n^3+n}2}[/tex]

From here it's easy to find S₇ and S₁₇.

[tex]S_7 = \dfrac{7^3+7}2 \implies \boxed{S_7 = 175}[/tex]

[tex]S_{17} = \dfrac{17^3+17}2 \implies \boxed{S_{17} = 2465}[/tex]

Answer:

Step-by-step explanation:

The rule when you divide two values with the same base is to subtract the exponents.

Answer:

4 tenths or 4/10

Step-by-step explanation:

Answer:

$20,000

Step-by-step explanation:

20,000 / 0.07 = 1400

Answers:

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

Explanation:

For equation A, I'll transform the right hand side into a similar form as the left side. Throughout the steps below, the left hand side stays the same.

[tex]\sqrt{448x^c} = 8x^3\sqrt{7x}\\\\\sqrt{448x^c} = \sqrt{(8x^3)^2}\sqrt{7x}\\\\\sqrt{448x^c} = \sqrt{64x^{3*2}}\sqrt{7x}\\\\\sqrt{448x^c} = \sqrt{64x^{6}}\sqrt{7x}\\\\\sqrt{448x^c} = \sqrt{64x^{6}*7x}\\\\\sqrt{448x^c} = \sqrt{64*7x^{6+1}}\\\\\sqrt{448x^c} = \sqrt{448x^{7}}\\\\[/tex]

Therefore, c = 7

Notice that 7/2 = 3 remainder 1. The quotient 3 is the exponent for the term outside the root for [tex]8x^3\sqrt{7x}[/tex] while the remainder 1 is the exponent for the x term inside the root.

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

We do the same idea for equation B.

[tex]\sqrt[3]{576x^{d}} = 4x\sqrt[3]{9x^{2}}\\\\\sqrt[3]{576x^{d}} = \sqrt[3]{(4x)^3}\sqrt[3]{9x^{2}}\\\\\sqrt[3]{576x^{d}} = \sqrt[3]{64x^3}\sqrt[3]{9x^{2}}\\\\\sqrt[3]{576x^{d}} = \sqrt[3]{64x^3*9x^{2}}\\\\\sqrt[3]{576x^{d}} = \sqrt[3]{64*9x^{3+2}}\\\\\sqrt[3]{576x^{d}} = \sqrt[3]{576x^{5}}\\\\[/tex]

This must mean d = 5

Note: 5/3 = 1 remainder 2, which means [tex]\sqrt[3]{x^5} = x^1\sqrt[3]{x^2} = x\sqrt[3]{x^2}[/tex]

Answer:

A. x²- 4x+ 1

option A is the answer

2b + 21 < 22

b is the unknown number so multiply it by 2 to get 2b then add 21, bring the less than sign and write the 22 after the less than sign

[tex]\text{Given that,}\\\\f(x) = 4x+5,~~~g(x) = \dfrac 2x\\\\\\f(3) = 4(3) +5 = 12 +5 = 17\\\\\\(g\circ f)(3)=g(f(3))=g(17)=\dfrac 2{17}[/tex]

Answer:

The answer is 2/17

Step-by-step explanation: Can I get brainliest again my answer was deletedee

Answer:

630

Step-by-step explanation:

the value of 7 in the tenths place is 70

the value of 7 in the hundredths place is 700

compare 700 and 70

So 700-70 = 630

22/3 sorry I accidentally deleted steps

Answer:

Hello There!

According to the question,

Base=6

And

Height =4

Let's know the formula

[tex] \frac{1}{2} \times base \times height \\ so \\ \frac{1}{2} \times 6 \times 4 \\ [/tex]

simplify 2 with 6 then it will look like this

[tex] \frac{1}{1} \times3 \times 4 \\ \\ [/tex]

1 has no value so

[tex]3 \times 4 = 12 {ft}^{2} \\ [/tex]

So third option

[tex]a = 12 {ft}^{2} [/tex]

is correct.

[tex]\Large\textsf{Hope \: It \: Helped}[/tex]

Answer:

Area = 12 sq ft

Step-by-step explanation:

The formula to find the area of a triangle is

1/2 bh so we will replace the letters with their number value

1/2 (6x4)

1/2 x 24 = 12

So, 12 is your answer!

Check the picture below.

The value of f(x) at x=4 is 2.

A function is an expression, rule, or law in mathematics that describes a relationship between one variable (the independent variable) and another variable (the dependent variable). Functions are common in mathematics and are required for the formulation of physical relationships in the sciences.

We have to find the value of function for x=4.

This means that from the figure we have to find the value of y when x= 4.

Now, looking into the figure we have

f(4)= 2

f(0)= -2

f(-1)= -1

f(3)= 4

So, the required value is 2.

Learn more about Function here:

https://brainly.com/question/12431044

#SPJ7

Answer:

x=sqrt(7)

Step-by-step explanation:

Since this is a right triangle, we can use the pythagorean theorem

a^2 + b^2 =c^2  where a and b are the legs and c is the hypotenuse

x^2 + ( sqrt(7))^2 = (sqrt(14))^2

x^2+7 = 14

x^2 = 14-7

x^2 = 7

Take the square root of each side

sqrt(x^2) = sqrt(7)

x=sqrt(7)

Answer:

B. 70

Step-by-step explanation:

If 199.50 PHP gets you 2.85KG of rice.

A kilogram of rice would cost = Total Amount / Total Weight.

199.50/2.85

= 70PHP

Answer:

[tex]-\frac{1}{4}(\sqrt{2}+\sqrt{6})[/tex]

Step-by-step explanation:

[tex]cos(\frac{11\pi}{12})[/tex]

[tex]cos(\frac{2\pi}{3}+\frac{\pi}{4})[/tex]

[tex]cos(\frac{2\pi}{3})cos(\frac{\pi}{4})-sin(\frac{2\pi}{3})sin(\frac{\pi}{4})[/tex]

[tex](-\frac{1}{2})(\frac{\sqrt{2}}{2})-(\frac{\sqrt{3}}{2})(\frac{\sqrt{2}}{2})[/tex]

[tex]-\frac{\sqrt{2}}{4}- \frac{\sqrt{6}}{4}[/tex]

[tex]-\frac{1}{4}(\sqrt{2}+\sqrt{6})[/tex]

Helpful Tips:

Sum Identity: [tex]cos(\alpha+\beta)=cos(\alpha)cos(\beta)-sin(\alpha)sin(\beta)[/tex]

Answer:

x=28°

Step-by-step explanation:

supplementary angles equal 180°

So:

3x+2x+x+12=180°

6x+12=180

6x=168

x=28°

Therefore:

3x:

3(28)=84°

2x:

2(28)=26°

x+12:

28+12=40°

Answer:

It's 48.

Hope that helped? Also, if you need anymore answers feel free to ask me as I had that assignment on Mathswatch.

Step-by-step explanation:

Answer:

i think it's 48 if i'm wrong i'm sorry

Answer:

7=4m +c( y intercept)

Step-by-step explanation:

use the formula y= mx +c

Using the midpoint formula, the coordinates of endpoint H are (4, -6).

The midpoint formula is given as: [tex](x_m, y_m) = (\frac{x_1 + x_2}{2}, \frac{y_1 + y_2}{2} )[/tex]

Where,

[tex](x_m, y_m)[/tex] = coordinates of the midpoint

[tex](x_1, y_1)[/tex] = coordinates of the first point

[tex](x_2, y_2)[/tex] = coordinates of the second point

Given the following:

[tex](x_m, y_m)[/tex] = M( 6,-4)

[tex](x_1, y_1)[/tex] = G(8,-2)

[tex](x_2, y_2)[/tex] = H(?, ?)

Plug in the values into the midpoint formula

[tex]M(6, -4) = (\frac{8 + x_2}{2}, \frac{-2 + y_2}{2} )[/tex]

Solve for the x-coordinate and y-coordinate separately

[tex]6 = \frac{8 + x_2}{2}[/tex]

[tex]6 \times 2 = 8 + x_2\\\\12 = 8 + x_2\\\\12 - 8 = x_2\\\\4 = x_2\\\\\mathbf{x_2 = 4}[/tex]

[tex]-4 = \frac{-2 + y_2}{2}\\\\-8 = -2 + y_2\\\\-8 + 2 = y_2\\\\-6 = y_2\\\\\mathbf{y_2 = -6}[/tex]

Therefore, using the midpoint formula, the coordinates of endpoint H are (4, -6).

Learn more about midpoint formula on:

https://brainly.com/question/13115533

Answer:

4

Step-by-step explanation:

-4+3=-1

-1+5=4

Answer:

7½ cups of sugar

Step-by-step explanation:

2 cups of flour needs 3 cups of sugar

1 cups of flour needs 3/2=1.5 cups of sugar

1×5 cups of flour needs 1.5×5=7.5 cups of sugar=7½ cups of sugar ANS

Answer:

DC

Step-by-step explanation:

If we rotate a segment around a point 360 degrees, we have rotated it around to its original point. Similarly, if we rotate it 180 degrees, we have rotated it to the side opposite of where it once was relative to the point.

What we can do is see how much 144 degrees is of 360 and use that to determine how far around we rotate AE around F.

144/360

divide by 12 because that is a common factor of both the numerator and denominator

12 / 30

divide by 2 because that is a common factor

6/15

divide by 3 because that is a common factor

2/5

Therefore, 144/360 = 2/5. This means that we rotate segment AE 2/5 of the way around point F. We have 5 sides in the polygon ABCDE, and each represents 1/5 of the way around. Going counterclockwise, ED represents 1/5, DC represents 2/5, and so on. We are looking for 2/5, so DC is our answer

Answer:

16:1

Step-by-step explanation:

Since there are 85 total people and 80 are students that means 5 are chaperones.(85-5) Therefore the ratio of students to chaperones is 80:5 or simplified 16:1.

Answer:

5x + 6 = 0

5x = - 6

x = - 6/5

-6/5 is the answer