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2 years ago

9x+10y =1 9x-6y=-15 solve using elimination

Mathematics

1 answer:

Nostrana [21]2 years ago

3 0

Answer:

I. x = -1

II. y = 1

Step-by-step explanation:

Given the following algebraic expressions;

9x + 10y = 1 .......equation 1

9x - 6y = -15 ......equation 2

To solve using the elimination method, we would subtract eqn 1 from eqn 2.

(9x - 9x) + (-6y - 10y) = (-15 - 1)

0x - 16y = -16

-16y = -16

16y = 16

y = 16/16

y = 1

Next, we would find the value of x;

From eqn 1;

9x + 10y = 1

Substituting the value of y, we have;

9x + 10(1) = 1

9x + 10 = 1

9x = 1 - 10

9x = -9

x = -9/9

x = -1

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Precal help if you could could you answer both. Me finishing this helps me graduate.

oee [108]

Exercise 1:

The easiest way to compute powers of complex numbers is to write them in the form

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In this form, you have

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The magnitude of the number is given by

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So, we have

$z=-1+\sqrt{3}i \implies \rho = \sqrt{1+3}=2$

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$z=a+bi \implies \theta = \text{atan2}\dfrac{b}{a}$

So, we have

$z=-1+\sqrt{3}i \implies \theta = \text{atan2}\left(\dfrac{-\sqrt{3}}{-1}\right) = -\dfrac{2\pi}{3}$

Finally,

$z=-1-\sqrt{3}i = 2\left(\cos\left( -\dfrac{2\pi}{3}\right) + i\sin\left( -\dfrac{2\pi}{3}\right)\right) \implies z^6 = 2^6\left(\cos\left( -4\pi\right) + i\sin\left(-4\pi\right)\right) = 64$

Exercise 2:

You simply have to compute the trigonometric function:

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7 0

3 years ago

A pharmacist wishes to mix a solution that is 6% Minoxidil. She has on hand 100 ml of a 2% solution and wishes to add some 8% so

son4ous [18]

Answer:

200 ml

Step-by-step explanation:

It's proportions basically.

frst off, 2% of 100 ml is 2 ml, so the 100 ml solution has 2 ml of Minoxidil.

Eventually we want 6/100 to be the porportion. so the total is going to be 100 (from the initial 100 ml) plus however much is needed x. And we want the amount of Minoxidil to be 2 + 8 percent of x. so this gets us the equation

6/100 = (2 + .08x)/(100+x) Then we solve

(100 + x) 6/100 = 2 + .08x

(100 + x) 6 = 200 + 8x

600 + 6x = 200 + 8x

400 = 2x

x = 200

so they should add 200 ml

You can check too. there is 100 + 200 ml of solution total and 2 + 16 ml of Minoxidil so that's 18/300 = 6/100

6 0

3 years ago

What is the equation of a line with an intercept of -3 and a slope of 5?

Setler79 [48]

Answer:

y= 5x-3

Step-by-step explanation:

We have an intercept of -3 and a slope of 5

We can use the slope intercept form of the equation

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Substituting in the known values.

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7 0

3 years ago

Which equations represent the line that is parallel to 3x − 4y = 7 and passes through the point (−4, −2)? Select two options. y

xz_007 [3.2K]

Answer:

The equation of the parallel line to the given equation is

3 x-4 y = -4 and

The equation of the parallel line to the given equation is

$y = 1 + \frac{3 x}{4}$

Step-by-step explanation:

Explanation:-

Given equation of the line 3 x -4 y = 7 and given point ( -4 , -2 )

The equation of the parallel line to the given equation is

3 x - 4 y = k

it is passes through the point ( -4 , -2)

3 (-4) - 4 ( -2) = k

-12 +8 = k

k = -4

The equation of the parallel line to the given equation is

3 x- 4 y = -4

Dividing '4' on both sides , we get

$\frac{3 x-4 y}{-4} = 1$

$\frac{-3 x}{4} +y =1$

$y = 1 + \frac{3 x}{4}$

Conclusion:-

∴ The equation of the parallel line to the given equation is

3 x- 4 y = -4

and

The equation of the parallel line to the given equation is

$y = 1 + \frac{3 x}{4}$

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Vera_Pavlovna [14]

Answer:

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2 years ago

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