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1 year ago

Which of these strategies would eliminate a variable in the system of equations?

Mathematics

1 answer:

mariarad [96]1 year ago

4 0

Answer:

Multiply the bottom equation by -3/2 then add the equations.

Multiply the top equation by-3. then add the equations

Step-by-step explanation:

Given the simultaneous equation

2x- 6y=6 ... 1

6x - 4y = 2 ... 2

To eliminate a variable, we have to make the coefficient of one of the variable to be the same.

Multiply equastion 1 by -3

-6x+18y= -18

6x - 4y = 2

Add the result:

-6x + 6x + 18y-4y = -18+2

18y-4y = -18+2

14y = -18

y = -9/7

Another way is to Multiply the bottom equation by -3/2 then add the equations.

Multiplying equation 2 by -3/2 will give;

6x(-3/2) - 4y(-3/2) = 2(-3/2)

-9x + 6y = -3

Add to equation 1;

2x- 6y=6

-9x + 2x + 0 = -3+6

-7x = 3

x = -3/7

Hence the correct two options are;

Multiply the bottom equation by -3/2 then add the equations.

Multiply the top equation by-3. then add the equations

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What is the answer to -8+5b= -6+26-9b

Slav-nsk [51]

Answer:

b=−1/14ot+2

Step-by-step explanation:

Let's solve for b.

to−8+5b=−6+26−9b

Step 1: Add 9b to both sides.

ot+5b−8+9b=−9b+20+9b

ot+14b−8=20

Step 2: Add -ot to both sides.

ot+14b−8+−ot=20+−ot

14b−8=−ot+20

Step 3: Add 8 to both sides.

14b−8+8=−ot+20+8

14b=−ot+28

Step 4: Divide both sides by 14.

14b

−ot+28

−1

ot+2

5 0

2 years ago

Expanded form of 5(2m)³

-BARSIC- [3]

Answer:

$40m^{3}$

Step-by-step explanation:

Because of order of operations, you do exponent first. $(2m)^{3} =8m^{3}$ . Lastly 8 multiplied by 5 is 40, so the answer is $40m^{3}$

6 0

1 year ago

Ten thousand times the sum of a number and seven hundred

Vera_Pavlovna [14]

Let x be the unknown number.

The sum of x and seven hundred is $x+700$

Ten thousand times this sum is $10000(x+700)$

5 0

2 years ago

A= [1, 3; 2, 1], B=[3, 6; -1, 1]. Find AB & BA if possible

steposvetlana [31]

Answer:

$AB\Rightarrow \quad \begin{bmatrix}0 & 9\\ 5 & 13\end{bmatrix}\\BA\Rightarrow \quad \begin{bmatrix}15 & 15\\ 1 & -2\end{bmatrix}$

Step-by-step explanation:

For two matrix P and Q, the product, say PQ is defined when:

The number of columns of P = The number of rows of Q

Since A is a 2×2 matrix and B is also a 2×2 matrix

Thus both AB and BA are possible.

So AB is:

$AB\Rightarrow\begin{bmatrix}1 & 3\\ 2 & 1\end{bmatrix}\begin{bmatrix}3 & 6\\ -1 & 1\end{bmatrix}\\AB\Rightarrow\quad \begin{bmatrix}3\times 1+3\times (-1) & 6\times 1+3\times 1\\3\times 2+1\times (-1) & 6\times 2+1\times 1\end{bmatrix}\\AB\Rightarrow \quad \begin{bmatrix}0 & 9\\ 5 & 13\end{bmatrix}$

BA is:

$BA\Rightarrow\begin{bmatrix}3 & 6\\ -1 & 1\end{bmatrix}\begin{bmatrix}1 & 3\\ 2 & 1\end{bmatrix}\\BA\Rightarrow\quad \begin{bmatrix}3\times 1+6\times 2 & 3\times 3+6\times 1\\(-1)\times 1+1\times 2 & (-1)\times 3+1\times 1\end{bmatrix}\\BA\Rightarrow \quad \begin{bmatrix}15 & 15\\ 1 & -2\end{bmatrix}$

8 0

2 years ago

Can someone help with this math pls, im confused and I don't know

baherus [9]

Answer:

So im also confused but I can provide you with some help :)

Step-by-step explanation:

the sum of a triangle is 180 degrees

Its in the first quadrant

Each letter reprents one point of the triangle which we can find by using cordinatnates on the chart

8 0

2 years ago