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3 years ago

Y=x+2 3x+3y=6 solving systems by substitution

Mathematics

1 answer:

motikmotik3 years ago

6 0

Answer:6

Step-by-step explanation:Reorder

and

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Replace all occurrences of

with

−

(

−

)

(

)

Simplify

(

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)

(

)

Tap for more steps...

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Since

, the equation will always be true.

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Always true

Remove any equations from the system that are always true.

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A correlation coefficient of _____ indicates that the variables form a perfect linear relationship.

serg [7]

A correlation coefficient of 1 or -1 indicates that the variables form a perfect linear relationship.

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3 years ago

Complete the page for 15 points.

sergey [27]

Answer:

1. 15, 16, 17

2. 21, 23, 25

3. 44, 46, 48

4. -4, -3, -2

Step-by-step explanation:

Step 1. Writing an equation

Let's set x as the second number in the equation.

This means that the first number is x-1, and the third number is x+1.

We know that the sum of the three numbers is 48, so:

(x-1)+x+(x+1)=48

Step 2. Solving the equation

x-1+x+x+1=48

x+x+x-1+1=48

3x=48

x=16

So the answer is 15, 16, 17

Again, let's set x as the middle number.

Odd numbers are 2 numbers apart, so the first number is x-2, and the third is x+2.

This means that the equation must be:

(x-2)+x+(x+2)=69

x+x+x=69

3x=69

x=23

The numbers are 21, 23, and 25

x will be the middle number

Even numbers are 2 numbers apart, so the first number is x-2, and the third is x+2.

This means that:

x-2+x+x+2=138

x+x+x=138

3x=138

x=46

The numbers are 44, 46, and 48.

x will be the middle number.

x-1=first number, x+1=third number

x-1+x+x+1=-9

3x=-9

x=-3

The numbers are -4, -3, and -2.

3 0

3 years ago

Using the figure below, write the ratio for tan (C). А 25 C 7 24 B

miv72 [106K]

Answer:

come have it with me

Step-by-step explanation:

4 0

3 years ago

The Parry Glitter Company recently loaned $300,000 to FIX 92, a local radio station. The radio station signed a noninterest-bear

melomori [17]

Answer:

The Parry Glitter Company

The Parry Glitter Company should record the Notes Receivable as $300,000.

It should also record the interest receivable per year as $24,000 and the advertising cost as $24,000 per year. These bring into the accounting records the interest revenue and also the advertising expense, which eventually cancel each other.

Step-by-step explanation:

a) Data and Calculations:

Notes Receivable = $300,000

If the notes receivable are repaid at the end of 3 years and it is assumed that the interest on the notes receivable = 8%

Therefore, the cost of the free advertising will be equal to $24,000 ($300,000 * 8%), which is the cost of the interest to the radio station.

8 0

3 years ago

Solve the following differential equation using using characteristic equation using Laplace Transform i. ii y" +y sin 2t, y(0) 2

kifflom [539]

Answer:

The solution of the differential equation is $y(t)= - \frac{1}{3} Sin(2t)+2 Cos(t)+\frac{5}{3} Sin(t)$

Step-by-step explanation:

The differential equation is given by: y" + y = Sin(2t)

i) Using characteristic equation:

The characteristic equation method assumes that y(t)= $e^{rt}$ , where "r" is a constant.

We find the solution of the homogeneus differential equation:

y" + y = 0

$y'=re^{rt}$

$y"=r^{2}e^{rt}$

$r^{2}e^{rt}+e^{rt}=0$

$(r^{2}+1)e^{rt}=0$

As $e^{rt}$ could never be zero, the term (r²+1) must be zero:

(r²+1)=0

r=±i

The solution of the homogeneus differential equation is:

$y(t)_{h}=c_{1}e^{it}+c_{2}e^{-it}$

Using Euler's formula:

$y(t)_{h}=c_{1}[Sin(t)+iCos(t)]+c_{2}[Sin(t)-iCos(t)]$

$y(t)_{h}=(c_{1}+c_{2})Sin(t)+(c_{1}-c_{2})iCos(t)$

$y(t)_{h}=C_{1}Sin(t)+C_{2}Cos(t)$

The particular solution of the differential equation is given by:

$y(t)_{p}=ASin(2t)+BCos(2t)$

$y'(t)_{p}=2ACos(2t)-2BSin(2t)$

$y''(t)_{p}=-4ASin(2t)-4BCos(2t)$

So we use these derivatives in the differential equation:

$-4ASin(2t)-4BCos(2t)+ASin(2t)+BCos(2t)=Sin(2t)$

$-3ASin(2t)-3BCos(2t)=Sin(2t)$

As there is not a term for Cos(2t), B is equal to 0.

So the value A=-1/3

The solution is the sum of the particular function and the homogeneous function:

$y(t)= - \frac{1}{3} Sin(2t) + C_{1} Sin(t) + C_{2} Cos(t)$

Using the initial conditions we can check that C1=5/3 and C2=2

ii) Using Laplace Transform:

To solve the differential equation we use the Laplace transformation in both members:

ℒ[y" + y]=ℒ[Sin(2t)]

ℒ[y"]+ℒ[y]=ℒ[Sin(2t)]

By using the Table of Laplace Transform we get:

ℒ[y"]=s²·ℒ[y]-s·y(0)-y'(0)=s²·Y(s) -2s-1

ℒ[y]=Y(s)

ℒ[Sin(2t)]= $\frac{2}{(s^{2}+4)}$

We replace the previous data in the equation:

s²·Y(s) -2s-1+Y(s) = $\frac{2}{(s^{2}+4)}$

(s²+1)·Y(s)-2s-1= $\frac{2}{(s^{2}+4)}$

(s²+1)·Y(s)= $\frac{2}{(s^{2}+4)}+2s+1=\frac{2+2s(s^{2}+4)+s^{2}+4}{(s^{2}+4)}$

Y(s)= $\frac{2+2s(s^{2}+4)+s^{2}+4}{(s^{2}+4)(s^{2}+1)}$

Y(s)= $\frac{2s^{3}+s^{2}+8s+6}{(s^{2}+4)(s^{2}+1)}$

Using partial franction method:

$\frac{2s^{3}+s^{2}+8s+6}{(s^{2}+4)(s^{2}+1)}=\frac{As+B}{s^{2}+4} +\frac{Cs+D}{s^{2}+1}$

2s^{3}+s^{2}+8s+6=(As+B)(s²+1)+(Cs+D)(s²+4)

2s^{3}+s^{2}+8s+6=s³(A+C)+s²(B+D)+s(A+4C)+(B+4D)

We solve the equation system:

A+C=2

B+D=1

A+4C=8

B+4D=6

The solutions are:

A=0 ; B= -2/3 ; C=2 ; D=5/3

So,

Y(s)= $\frac{-\frac{2}{3} }{s^{2}+4} +\frac{2s+\frac{5}{3} }{s^{2}+1}$

Y(s)= $-\frac{1}{3} \frac{2}{s^{2}+4} +2\frac{s }{s^{2}+1}+\frac{5}{3}\frac{1}{s^{2}+1}$

By using the inverse of the Laplace transform:

ℒ⁻¹[Y(s)]=ℒ⁻¹[ $-\frac{1}{3} \frac{2}{s^{2}+4}$ ]-ℒ⁻¹[ $2\frac{s }{s^{2}+1}$ ]+ℒ⁻¹[ $\frac{5}{3}\frac{1}{s^{2}+1}$ ]

$y(t)= - \frac{1}{3} Sin(2t)+2 Cos(t)+\frac{5}{3} Sin(t)$

3 0

3 years ago