X-Y=9 and 2X+5Y=4 solve by substitution

[tex](i)\\\\2A = \begin{pmatrix}3x \times 2 & 1 \times 2 & 5 \times 2\\0\times 2 & 2x \times 2 & -3 \times 2\end{pmatrix} = \begin{pmatrix}6x & 2 & 10\\0 & 4x & -6\end{pmatrix}\\\\\\(ii)\\\\2A + B = C\\\\\implies \begin{pmatrix}6x & 2 & 10\\0 & 4x & -6\end{pmatrix} + \begin{pmatrix}y & 0 & -4\\1 & -3y & 2\end{pmatrix} = \begin{pmatrix}31& 2 & 6\\1 & 17& -4\end{pmatrix}[/tex]

[tex]\implies \begin{pmatrix}6x+y & 2+0 & 10-4\\0+1 & 4x-3y & -6+2\end{pmatrix} = \begin{pmatrix}31 & 2 & 6\\1 & 17& -4 \end{pmatrix}\\\\\\\implies \begin{pmatrix}6x+y & 2 & 6\\1 & 4x-3y & -4\end{pmatrix} = \begin{pmatrix}31 & 2 & 6\\1 & 17& -4 \end{pmatrix}\\\\\text{System of equations},\\\\6x +y =31,~~ 4x -3y = 17\\\\\\(iii)\\\\6x +y-31 =0 \\\\4x-3y -17=0\\\\\text{Solving by cross multiplication method}\\\\\\\dfrac x{1(-17) - (-31)(-3)} = \dfrac y{4(-31) - 6(-17)} = \dfrac 1{6(-3) - 4(1)}[/tex]

[tex]\implies \dfrac{x}{-17 -93} = \dfrac{y}{-124 +102} = \dfrac 1{-18-4}\\\\\\\implies -\dfrac{x}{110} = -\dfrac{y}{22} = -\dfrac 1{22}\\\\ \implies \dfrac{x}{110} = \dfrac{y}{22} = \dfrac 1{22}\\\ \\\text{Hence,}\\\\\\x=\dfrac{110}{22}=5,~~~~ y= \dfrac{22}{22} =1[/tex]

Answer:

  (i)

  [tex]2A=\left[\begin{array}{ccc}6x&2&10\\0&4x&-6\end{array}\right][/tex]

  (ii) 6x+y=31; 4x-3y=17

  (iii) (x, y) = (5, 1)

Step-by-step explanation:

The matrix 2A is written by multiplying each element of A by 2.

  [tex]2A=\left[\begin{array}{ccc}6x&2&10\\0&4x&-6\end{array}\right][/tex]

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Variables are seen in elements (1, 1) and (2, 2) of the matrices A and B, so the simultaneous equations can be chosen from those elements of the equation 2A+B=C.

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A graphing calculator shows the solution to be (x, y) = (5, 1).

z²-2i=0

Answer:

Solution given:

z⁴=-4

doing square root on both side

[tex]\sqrt{z⁴}=\sqrt{2²*-1}[/tex]

we know i²=-1

substituting i² we get

z²=[tex]\sqrt{2²*i²}[/tex]

z²=2i

z²-2i=0 is a required answer. where

z² and 2 is real number.

Answer:

  z = {-1 -i, -1 +i, 1 -i, 1 +i}

Step-by-step explanation:

Using Euler's formula, we can write the equation as ...

  z^4 = 4e^(i(π +2πn)) . . . . . . where n is any integer

Then the 4th root is ...

  z = (√2)e^(i(π +2πn)/4 = (√2)e^(i(π/4 +nπ/2)) . . . . . for n = 0–3

  z = √2(cos(π/4+nπ/2) +i·sin(π/4 +nπ/2)) . . . . . for n = 0–3

  z = ±1 ±i

  z = {1 +i, -1 +i, -1 -i, 1 -i}

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Additional comment

Values of n are only needed in the range 0–3, because the answers repeat for values other than those.

Answer:

cant see

Step-by-step explanation:

Answer in the pic hope it helps

Answer:

y=6+8

y=14

Step-by-step explanation:

y=14 is the answer to this question

Answer:

8:10

Step-by-step explanation:

8 parts for brown sugar and 10 parts flour.

In simplest, 4:5 (divide 8 and 10 by 2)

Answer:y=4x+4

Step-by-step explanation:

Step-by-step explanation:

If you swim 575 yards in 3 days, you swim 575 yards.

If you swim 575 yards per day for 3 days, then you swim 3 × 575 yd = 1725 yd

Answer:

114

x_shun

jdebh

jejeu

Answer:

2 lines are used fro their respected two centers one Is vertical or one is horizontal it's dice into 4 squares

Answer:

13/6 or 2 1/6 is a fraction and is rational number, so yes it is rational

In the original equation, x is a variable, hence f(x). If that term in the parenthesis changes, such as to 0 or -2, we will plug in that number in place of the current variable.

f(0) = 4(0)^2 + 3 = 0 + 3 = 3

f(-2) = 4(-2)^2 + 3 = 4(4) + 3 = 16 + 3 = 19

Hope this helps! :)

Answer:96

Step-by-step explanation:

Step-by-step explanation:

1- 2x(x -4)

2- 3x(2-3x)

3- 4x²(3x-1)

Answer:

1/4 or .25

Step-by-step explanation:

You cross multiply which would give you 4x=1.

Answer:

r = -28/9

Step-by-step explanation:

use slope formula of (y₂-y₁) / (x₂-x₁)

5/9 = [r - (-2)] / [-7 - (-5)]

5/9 = (r+2) /-2

cross-multiply to get:

-2(5) = 9(r+2)

-10 = 9r + 18

-28 = 9r

r = -28/9

Answer:

Draw a straight line through these two points (0, 0) and (1, 3).

Step-by-step explanation:

"Proportional relationship" implies line or curve that goes through the origin; there is no "y-intercept" in this case.  

Plot a dot at (0, 0).  Next, move your pencil point 1 unit to the right (you'll end up at (1, 0), and then move it from there up to (1, 3).  Draw a straight line through these two points (0, 0) and (1, 3).

Answer:

A.-4x^2y^4

that the answer

Answer: yes

Step-by-step explanation:

It is because for every x value there is a y and the x value does not repeat to any y values.

Answer:

No because the slope isnt constant, the y changes higher and higher while the x stays constant

Step-by-step explanation:

Hope this helps!:)

Answer:

A

Step-by-step explanation:

[tex]\huge \sf༆ Answer ༄[/tex]

Let's solve ~

Hence, the correct choice is ~ A

Answer:

y=2(x+5)^2-4.

Step-by-step explanation:

By solving a little bit, we get the vertex to be (-5, -4). Plugging the info given and the vertex into the vertex form, we get y=2(x+5)^2-4. You have a happy holiday season, too!

Answer: 49/30 or, 1 19/30

Answer: slope (m) = -2

Step-by-step explanation:

y-3=-2(x+5)

put it into y=mx+b

use PEMDAS-Parantheses, Exponents, Mult. Div. Add. Sub. for your order of operations.

first, parantheses.

-2(x+5)

-2 times x = -2x

-2 times 5 = -10

your new equation is y-3 = -2x-10

now, to get y by itself, cancel out the -3 by adding a positive 3 to both sides.

you final equation will be y=-2x-7

in the form y=mx+b, m is your slope.

therefore, -2 is your answer, or slope.

Answer:

54 km/h

Step-by-step explanation:

use s=½(u+v)t

600=½(x+x+12)10

600=½(2x+12)10

600=(2x+12)5

600=10x+60

540=10x

x=54 km/h

I think this is how to do it, I'm so sorry if I do it wrong!

Answer:

See image

Step-by-step explanation:

Simple way: The cost of three items is given. Divide by 3 to find the cost of one item.

Next level: write a proportion by comparing like quantities (compare things that are the same in the same order)

Cost/numbers of items = Cost/number of items

We know all but one piece of information:

4.76/3 = x/1

Solve for x to find the price of one carton.

Answer:

A. 4

Step-by-step explanation:

Answer:

A

Step-by-step explanation:

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

Explanation:

Let's focus on the root x = 2i. Square both sides to get rid of the imaginary component and then get everything to one side.

x = 2i

x^2 = (2i)^2

x^2 = 4i^2

x^2 = -4

x^2+4 = 0

You should find that the root x = -2i leads to x^2+4 = 0 as well.

So the equation x^2+4 = 0 produces the complex roots x = 2i and x = -2i. This tells us that x^2+4 is a factor of the answer. The other factor is x-5 due to the real number root x = 5.

We'll multiply those two factors mentioned:

(x-5)(x^2+4)

w(x^2+4) ..... let w = x-5

wx^2 + 4w

x^2(w) + 4(w)

x^2(x-5) + 4(x-5) .... plug in w = x-5

x^3 - 5x^2 + 4x - 20

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The last step is to triple each term so that we go from the leading term of x^3 to 3x^3. This will give us a lead coefficient of 3.

So we go from this

x^3 - 5x^2 + 4x - 20

to this

3x^3 - 15x^2 + 12x - 60

after tripling everything. This expression has the same roots as the previous one. Scaling the function only stretches it vertically, but the roots aren't changed.

Answer:

65 hot dogs, 96 sodas

Step-by-step explanation:

x + (x + 31) = 161

2x + 31 = 161

2x = 130

x = 65

65 hotdogs

65 + 31 = 96

96 sodas

Answer:

$237.50

Step-by-step explanation:

5/100=.05

250•.05=12.5

250-12.5=237.50