Please help me with this

If the given equations are indeed

[tex]\begin{cases}x-\frac4{5y} = 9\frac45 \\ -14x - 4y = -46\end{cases}[/tex]

we can solve by substitution. Solve the second equation for x :

[tex]-14x - 4y = -46[/tex]

[tex]\implies 7x + 2y = 23[/tex]

[tex]\implies7x = 23 - 2y[/tex]

[tex]\implies x = (23 - 2y)/7[/tex]

Substitute this into the first equation and solve for y :

[tex]\dfrac{23-2y}7 - \dfrac4{5y} = 9\dfrac45[/tex]

On the right side, write the mixed number as an improper fraction:

[tex]9 + \dfrac45 = \dfrac{45}5 + \dfrac45 = \dfrac{45+4}5 = \dfrac{49}5[/tex]

[tex]\implies \dfrac{23-2y}7 - \dfrac4{5y} = \dfrac{49}5[/tex]

Multiply both sides of this equation by 35y (the LCM of the denominator of all three fractions)

[tex]35y \times \dfrac{23-2y}7 - 35y \times \dfrac4{5y} = 35y \times \dfrac{49}5[/tex]

[tex]5y\times(23-2y) - 7\times4 = 7y \times 49[/tex]

[tex]115y - 10y^2 - 28 = 343y[/tex]

[tex]10y^2 + 228y + 28 = 0[/tex]

[tex]5y^2 + 114y + 14 = 0[/tex]

To solve the quadratic, I'll complete the square :

[tex]5\left(y^2 + \dfrac{114}5y\right) + 14 = 0[/tex]

[tex]5\left(\left(y + \dfrac{57}5\right)^2 - \left(\dfrac{57}5\right)^2 \right) + 14 = 0[/tex]

[tex]5\left(y + \dfrac{57}5\right)^2 - \dfrac{57^2}5 + 14 = 0[/tex]

[tex]5\left(y + \dfrac{57}5\right)^2 = -\dfrac{3179}5[/tex]

This system has no real solutions since the square of any real number must be positive.

If we allow complex numbers, we can continue solving to end up with two complex solutions for y,

[tex]\left(y + \dfrac{57}5\right)^2 = -\dfrac{3179}{25}[/tex]

[tex]y + \dfrac{57}5 = \pm i \sqrt{\dfrac{3179}{25}}[/tex]

[tex]y = -\dfrac{57}5 \pm i\dfrac{17\sqrt{11}}5[/tex]

and we can go on to solve for x.

Hence my comment; I suspect you meant to write the system

[tex]\begin{cases}x-\frac45 y = 9\frac45 \\ -14x - 4y = -46\end{cases}[/tex]

because its solution is far simpler. Multiplying through the first equation by 5 gives

[tex]5\times x - 5 \times \dfrac45 y = 5 \times 9\dfrac45[/tex]

[tex]\implies 5x - 4y = 49[/tex]

(since we know 9 + 4/5 = 49/5)

Meanwhile, multiplying through the second equation by -1 gives

[tex]-1 \times (-14x) + (-1) \times (-4y) = -1 \times (-46)[/tex]

[tex]\implies 14x + 4y = 46[/tex]

So if we combine the two equations, we can eliminate y and solve for x :

[tex](5x - 4y) + (14x + 4y) = 49 + 46[/tex]

[tex]\implies 19x = 95[/tex]

[tex]\implies \boxed{x = 5}[/tex]

and solving for y gives

[tex]14x + 4y = 46[/tex]

[tex]\implies 70 + 4y = 46[/tex]

[tex]\implies 4y = -24[/tex]

[tex]\implies \boxed{y = -6}[/tex]

Answer:

  0.8646

Step-by-step explanation:

The digit in the hundred-thousandths place is 9, so is greater than 4. That means the digit in the ten-thousandths place is increased by 1 when the number is rounded.

  0.864595 rounds to 0.8646

Answer:

x=141

Step-by-step explanation:

The measure of all the angles in a septagon (7 sided shape) add up to 900°. The current sum of the known angles 131°+122°+125°+148°+107°+126°=759°.

900° total sum minus known sum 759° equals 141°.

Answer:

×=40

Step-by-step explanation:

The total value of all the angles on any line is 180

so x+(4x-20)=180

40+(4×40-20)=180

Answer:

40°

Step-by-step explanation:

The sum of angles x and (4x - 20) is 180°

x + (4x - 20) = 180

5x = 200

x = 40°

Answer:

y = -4x + 2

Step-by-step explanation:

Step-by-step explanation:

Hope It Helps You

Here You Answer

Answer:

C. 252 miles.

Step-by-step explanation:

Since we already know how many miles is driven for 10 gallons of gas, we only need to find 2.

Since 105 miles runs on 5 gallons, divide 105 by 5 to find out how many miles runs on 1 gallon.

105/5=21

Then, multiply that by 2 to find out how many miles run on 2 gallons of gas.

21x2=42.

Finally, add 42 to 210 to get the amount of miles that runs on 12 gallons of gas.

210+42=252

Answer:

240

Step-by-step explanation:

36+4=40

40x6=240

Answer:

-2

Step-by-step explanation:

Answer:

28

Step-by-step explanation:

Put in calculator 28-33= -5

Answer:

The concept of identity, the meaning we give to ourselves and our sense of purpose, connects us to others. This concept best illustrates the link between the psychological and ____ system

Answer:

The answer is 4.5 cups I hope this helps :D

Answer:

Yup ur Right ;D

Step-by-step explanation:

Answer:

a) Draw a line horizontally on 4 on the y axis

b)x=2,y=3

Answer: 5, 7/2

Step-by-step explanation:

2x − 4y = -4

3x + 2y = 22

divide both sides of the equation by 2

 x − 2y = -2

3x + 2y = 22

Eliminate one variable by adding the equation;  sum the equations vertically to eliminate at least one variable

4x=20

Divides both sides by 4

x=5

Substitute  the given value of x into the equation 2x-4y = -4

2*5-4y =-4

solve the equation for y

y=7/2

Answer:

(100-12) - 3

Step-by-step explanation:

we dont know what the cost of the shirts are so that one should be it.

Step-by-step explanation:

get add and add on ok

Answer:

Step-by-step explanation:

add up to a total of 21 girls. The question says there are 19 girls, so those two are eliminated. Table B's data doesn't even add properly so that is eliminated too

Answer:

Add up the 21 girls,

table B is out btw

Ik I'm late just want to help :)

Answer:

none of theses choices. wesley makes $2185 this month

Step-by-step explanation:

Answer: 27[tex]a^{-6}b^{3}[/tex]

Step-by-step explanation:

you can isolate the separate terms so you get

3^3 x a^(-2x3) x b^3 = 27 a^-6b^3

Answer:

the jar of peanut butter is $2.36

Step-by-step explanation:

Answer: $2.36

Step-by-step explanation:

Answer:

31-13=18

Step-by-step explanation:

so its 18 pls give brainliest

Answer:

18

Step-by-step explanation:

Since Robyn bought 13 video games and got 31 at the end, if you take away 13 then you will get 18 meaning the answer is 18

Maths Sum:

There's 2 ways you could go this, there's the algebraic way of doing it (that I don't recommend for this type of question and is a bit to advanced right for this question also) which is:

x + 13 = 31

  - 13   -13

x = 18

And there's the simple way of doing that I recmmend for this type of question which is:

31 - 13 = 18

[tex]\huge\boxed{Hi\:there!}[/tex]

[tex]\huge\sf{3x=9^2}[/tex]

[tex]\huge\sf{3x=81}[/tex]

[tex]\huge\sf{Divide\:both\:sides\:by\:3\:to\:isolate\:x:}[/tex]

[tex]\huge\sf{x=27}[/tex]

[tex]\huge\boxed{Hence,\:x=27.}[/tex]

[tex]\huge\sf\underline{Hope\:it\:helps}[/tex]

[tex]\boxed{CheerfulGirlie\:here\:to\:help}[/tex]

Find the value of x

3x = 9²

x = 27

=> 3x = 9²

=> 3x = 81 [9² = 9×9 = 81]

=> x = 81/3

=> x = 27

AB=EF

ABEF=ABF+AEF

NOW CONTINUES THE SOLUTION

Answer:

The answer should be 72.

Step-by-step explanation:

You're finding the interest earned. I = Prt, I for simple interest, P for principal, r for rate, and t for time.

Substitute p for $800, r for 9%, and t for is 1 year.

You would multiply these three numbers together.

$800(0.09)(1) should give you 72.

Answer:

8

Step-by-step explanation:

4*3*2*1 i had the same problem

The number of different ways the students can stand in line is A = 24 ways

A permutation is an ordered arrangement.

The number of ordered arrangements of r objects taken from n unlike objects is:

Permutation ⁿPr = n! / ( n - r )!

Given data ,

Let the number of different ways the students can stand in line be A

Now , There are 4 students to choose from for the first position in the line, then 3 remaining students for the second position, 2 remaining students for the third position, and only 1 student left for the last position.

Therefore, there are

4 × 3 × 2 × 1 = 24 different ways for the students to stand in line

Therefore , the value of A = 24 ways

Hence , the students have 24 ways to stand in line

To learn more about permutation click :

https://brainly.com/question/1216161

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