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3 years ago

Help me please I do not understand it.

Mathematics

1 answer:

fiasKO [112]3 years ago

4 0

6x - 11 + 15x + 2 = 180

21x - 9 = 180

21x = 189

x = 9

—

D = 15(9) + 2

D = 135 + 2

D = 137

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For a given input value q, the function f outputs a value r to satisfy the following equation. 11q-4=3r-6, Write a formula for f

Jlenok [28]

Q=2, r=8
11(2)= 3(8)-2
22=24-2
22

7 0

3 years ago

Read 2 more answers

Which are correct representations of inequality 6x>3+4(2x-1)

abruzzese [7]

The correct representations of inequality 6x>3+4(2x-1) will be 6x ≥ 3 + 8x – 4.Option B is correct

<h3>What is the definition of inequality?</h3>

Inequality is a sort of equation in which the equal sign is missing. As we will see, inequality is defined as a statement regarding the relative magnitude of two claims.

The complete question is;

"Which are correct representations of the inequality 6x ≥ 3 + 4(2x – 1)? Check all that apply.

A)1 ≥ 2x

B)6x ≥ 3 + 8x – 4"

6x ≥ 3 + 4(2x – 1)

6x≥3+8x-4

The correct representations of inequality 6x>3+4(2x-1) will be 6x ≥ 3 + 8x – 4.

Hence, option B is correct

To learn more about inequity, refer to brainly.com/question/20383699

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4 0

2 years ago

Patrick earns $40 per hour. He earned an extra $1000 for working on a special project. His pay check for the month was 7420. How

Likurg_2 [28]

Patrick worked 160.5 hours because you have to subtract 1000 from 7420 then divide that by 40 for your answer. Also, Patrick has a sweet job.

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3 years ago

Read 2 more answers

A boat crew rowed 10.5 miles downstream, with the current, in 1.5 hours. the return trip upstream , against the current , covere

alukav5142 [94]

Answer:

The speed of the boat is 5 miles per hours

The speed of the current is 2 miles per hours .

Step-by-step explanation:

Given as :

The distance cover by boat downstream = D = 10.5 miles

The time taken by boat to cover D distance = T = 1.5 hours

The distance cover by boat Upstream = d = 10.5 miles

The time taken by boat to cover d distance = t = 3.5 hours

Let The speed of boat = x mph

Let The speed of current = mph

Now, According to question

∵ Speed = $\dfrac{Distance}{Time}$

<u>For Downstream</u>

x + y = $\dfrac{D}{T}$

Or, x + y = $\dfrac{10.5}{1.5}$

Or, x + y = 7 .......A

<u>For Upstream</u>

x - y = $\dfrac{d}{t}$

Or, x - y = $\dfrac{10.5}{3.5}$

Or, x - y = 3 .......B

Now, Solving eq A and eq B

So, (x + y) + (x - y) = 7 + 3

Or, (x + x) + (y - y) = 10

Or, 2 x + 0 = 10

∴ x = $\dfrac{10}{2}$

i.e x = 5 mph

So, The speed of the boat = x = 5 miles per hours

Put the value of x into eq A

∵ x + y = 7

Or, 5 + y = 7

∴ y = 7 - 5

i.e y = 2 mph

So, The speed of the current = y = 2 miles per hours

Hence, The speed of the boat is 5 miles per hours and The speed of the current is 2 miles per hours . Answer

7 0

3 years ago

Can somebody explain how these would be done? The selected answer is incorrect, and I was told "Nice try...express the product b

trapecia [35]

Answer:

Solution ( Second Attachment ) : - 2.017 + 0.656i

Solution ( First Attachment ) : 16.140 - 5.244i

Step-by-step explanation:

Second Attachment : The quotient of the two expressions would be the following,

$6\left[\cos \left(\frac{2\pi }{5}\right)+i\sin \left(\frac{2\pi \:}{5}\right)\right]$ ÷ $2\sqrt{2}\left[\cos \left(\frac{-\pi }{2}\right)+i\sin \left(\frac{-\pi \:}{2}\right)\right]$

So if we want to determine this expression in standard complex form, we can first convert it into trigonometric form, then apply trivial identities. Either that, or we can straight away apply the following identities and substitute,

( 1 ) cos(x) = sin(π / 2 - x)

( 2 ) sin(x) = cos(π / 2 - x)

If cos(x) = sin(π / 2 - x), then cos(2π / 5) = sin(π / 2 - 2π / 5) = sin(π / 10). Respectively sin(2π / 5) = cos(π / 2 - 2π / 5) = cos(π / 10). Let's simplify sin(π / 10) and cos(π / 10) with two more identities,

( 1 ) $\cos \left(\frac{x}{2}\right)=\sqrt{\frac{1+\cos \left(x\right)}{2}}$

( 2 ) $\sin \left(\frac{x}{2}\right)=\sqrt{\frac{1-\cos \left(x\right)}{2}}$

These two identities makes sin(π / 10) = $\frac{\sqrt{2}\sqrt{3-\sqrt{5}}}{4}$ , and cos(π / 10) = $\frac{\sqrt{2}\sqrt{5+\sqrt{5}}}{4}$ .

Therefore cos(2π / 5) = $\frac{\sqrt{2}\sqrt{3-\sqrt{5}}}{4}$ , and sin(2π / 5) = $\frac{\sqrt{2}\sqrt{5+\sqrt{5}}}{4}$ . Substitute,

$6\left[ \left\frac{\sqrt{2}\sqrt{3-\sqrt{5}}}{4}+i\left\frac{\sqrt{2}\sqrt{5+\sqrt{5}}}{4}\right]$ ÷ $2\sqrt{2}\left[\cos \left(\frac{-\pi }{2}\right)+i\sin \left(\frac{-\pi \:}{2}\right)\right]$

Remember that cos(- π / 2) = 0, and sin(- π / 2) = - 1. Substituting those values,

$6\left[ \left\frac{\sqrt{2}\sqrt{3-\sqrt{5}}}{4}+i\left\frac{\sqrt{2}\sqrt{5+\sqrt{5}}}{4}\right]$ ÷ $2\sqrt{2}\left[0-i\right]$

And now simplify this expression to receive our answer,

$6\left[ \left\frac{\sqrt{2}\sqrt{3-\sqrt{5}}}{4}+i\left\frac{\sqrt{2}\sqrt{5+\sqrt{5}}}{4}\right]$ ÷ $2\sqrt{2}\left[0-i\right]$ = $-\frac{3\sqrt{5+\sqrt{5}}}{4}+\frac{3\sqrt{3-\sqrt{5}}}{4}i$ ,

$-\frac{3\sqrt{5+\sqrt{5}}}{4}$ = $-2.01749\dots$ and $\:\frac{3\sqrt{3-\sqrt{5}}}{4}$ = $0.65552\dots$

= $-2.01749+0.65552i$

As you can see our solution is option c. - 2.01749 was rounded to - 2.017, and 0.65552 was rounded to 0.656.

________________________________________

First Attachment : We know from the previous problem that cos(2π / 5) = $\frac{\sqrt{2}\sqrt{3-\sqrt{5}}}{4}$ , sin(2π / 5) = $\frac{\sqrt{2}\sqrt{5+\sqrt{5}}}{4}$ , cos(- π / 2) = 0, and sin(- π / 2) = - 1. Substituting we receive a simplified expression,

$6\sqrt{5+\sqrt{5}}-6i\sqrt{3-\sqrt{5}}$

We know that $6\sqrt{5+\sqrt{5}} = 16.13996\dots$ and $-\:6\sqrt{3-\sqrt{5}} = -5.24419\dots$ . Therefore,

Solution : $16.13996 - 5.24419i$

Which rounds to about option b.

7 0

3 years ago