Solve the quadratic equation. 22 – 9 = 16​

Answer:

[tex]\huge\boxed{x\in\left\{\dfrac{\pi}{6};\ \dfrac{\pi}{2}\ \dfrac{3\pi}{2};\ \dfrac{5\pi}{6}\right\}}[/tex]

Step-by-step explanation:

[tex]\cos x=\sin2x\qquad|\text{use}\ \sin\theta=2\sin\theta\cos\theta\\\\\cos x=2\sin x\cos x\qquad|\text{subtract}\ \cos x\ \text{from both sides}\\\\0=2\sin x\cos x-\cos x\\\\2\sin x\cos x-\cos x=0\qquad|\text{distribute}\\\\\cos x(2\sin x-1)=0\iff\underbrace{\cos x=0}_{(1)}\ \vee\ \underbrace{2\sin x-1=0}_{(2)}[/tex]

[tex](1)\\\cos x=0\Rightarrow x=\dfrac{\pi}{2}+k\pi;\ k\in\mathbb{Z}[/tex]

[tex](2)\\2\sin x-1=0\qquad|\text{add 1 to both sides}\\\\2\sin x=1\qquad|\text{divide sides by 2}\\\\\sin x=\dfrac{1}{2}\Rightarrow x=\dfrac{\pi}{6}+2k\pi\ \vee\ x=\dfrac{5\pi}{6}+2k\pi[/tex]

[tex]\text{From}\ (1)\ \text{and}\ (2)\ \text{we have}\\\\x=\dfrac{\pi}{2}+k\pi\ \vee\ x=\dfrac{\pi}{6}+2k\pi\ \vee\ x=\dfrac{5\pi}{6}+2k\pi\\\\\text{We have the interval}\ x\in[0;2\pi).\ \text{Therefore the solution is:}\\\\x\in\left\{\dfrac{\pi}{6};\ \dfrac{\pi}{2}\ \dfrac{3\pi}{2};\ \dfrac{5\pi}{6}\right\}[/tex]

Answer:

6/n^2

Step-by-step explanation:

I'm assuming it's an expression.

Answer:

21111

Step-by-step explanation:

2222

Answer:

[tex]y=\frac{1}{4}(x)+2[/tex]

you can write this as

[tex]f(x)=\frac{1}{4}x+2[/tex]

Step-by-step explanation:

2 points

(-4,1)(0,2)

[tex]y=\frac{1}{4}x+2[/tex] is the equaction of the line thats in the grapj

Why and How I got it?

you had 2 points, so you can using the slope equaction

Rise over run

why is slope important?

using the y incept equactions

y=mx+b, where slope is m

so you get slope you got m

Solve

rise over run

[tex]\frac{2-1}{0-(-4)}[/tex]

so you get

[tex]y=\frac{1}{4}x+b[/tex]

How do you get B?

you plug 1 points in

[tex]-4=\frac{1}{4}(1)+b[/tex]

Hoped this helped ya

<3

Answer:

1hr = 60min

3hr = 180min

the missing value is 180

Answer: the answer is A

Hope this is helpful

Step-by-step explanation:

I jus know

Answer:

(3,4)

Step-by-step explanation:

Answer:

The concentration of pollutants in the water can be defined as the quotient between the mass of pollutants and the total mass of water.

Assuming that 1L of water weighs 1000 grams, we know that:

Mass of pollutants = 5mg = 0.005g.

Initial concentration = 0.005g/1000g = 0.000005

If we multiply this by 100%, we get the percentage:

0.000005*100% = 0.0005%

Now, the mass of pollutants decreases by 10% each hour.

So if initially, we have 5mg

After one hour, we will have: 5mg - 0.1*5mg = 5mg*(0.9).

After another hour, we will have: 5mg*(0.9) - 0.1*5mg*0.9 = 5mg*(0.9)^2.

And so on, then after n hours, the mass of pollutants will be:

M(n) = 5mg*(0.9)^n

Or we can write this in grams as:

M(n) = 0.005g*(0.9)^n

Then the concentration as a function of time in hours will be:

C(n) = M(n)/1000g = (0.005g/1000g)*(0.9)^n

Notice that the thing between the parentheses is the initial concentration, then if we write this in percentage form:

c(n) = 100%*(0.005g/1000g)*(0.9)^n = 0.0005%*(0.9)

The function that represents the concentration of polution in the water as a function of hours is:

c(n) = 0.0005%*(0.9)

Answer:

258m

Step-by-step explanation:

This is a guess, if you could, please post your answer again, but this time click the paperclip icon, and add a screenshot of the figure!

Answer:

15

Step-by-step explanation:

Order of operations: Parentheses, Exponents, Multiplication, Division, Addition/Subtraction

We'll start with division first. 10/2 = 5, 3/3 = 1

Then, we'll add the terms left. 5 + 3 + 6 + 1 = 15

Answer:

D. 2/15

Step-by-step explanation:

6+4+3+2=15

Red is 2.

2/15

Answer:

please I need help......gjmtjmgj?hi?tmzdthwyriyotul!tkht

Answer:

18xy-2x-5y-8

Step-by-step explanation:

Просто умножьте,то что было в скобках

Answer:

-13824

Step-by-step explanation:

LK + KJ = 43

LK + 25 = 43

LK = 43 - 25

LK = 18

_________________________________

And we're done.....♥️♥️♥️♥️♥️

Answer:

(8×3)-63

just trust me that the right answer

Answer: Eric earns $37.50 per day.

Step-by-step explanation:

7.50(5)= 37.50

Answer:

R;2 B;1 P;

Step-by-step explanation:

R is red there are 2 reds

B is blue there are 1 blues

P is purple there are 1 purples

Given:

This table shows the ratio of apples to oranges.

Apples      Oranges

   6                 10

   9                 15

  12                  ?

To find:

The missing value in the table of equivalent ratios.

Solution:

Let the missing value be x.

The ratios of apple and oranges are equivalent. So,

[tex]\dfrac{6}{10}=\dfrac{9}{15}=\dfrac{12}{x}[/tex]

[tex]\dfrac{3}{5}=\dfrac{3}{5}=\dfrac{12}{x}[/tex]

[tex]\dfrac{3}{5}=\dfrac{12}{x}[/tex]

On cross multiplication, we get

[tex]3\times x=12\times 5[/tex]

[tex]3x=60[/tex]

Divide both sides by 3.

[tex]x=20[/tex]

Therefore, the missing value is 20.

Answer:

20

Step-by-step explanation:

hope it helps

Answer:

C. from step 2 to step 3

Answer:

The average of 20 numbers is zero. Of them, at the most, how many may be greater than zero? Average of 20 numbers = 0. Therefore Sum of 20 numbers = (0 x 20) = 0 It is quite possible that 19 of these numbers may be positive and if their sum is a, then 20th number is (-a).

Step-by-step explanation:

Answer:

x= -1.22

Step-by-step explanation:

I think in this case you would be solving for x. So, to start you would expand the 2 out to the (x-3). That would give you 2x-6. Then you would expand the 7 out to the (x+2). That would give you 7x+14. You would then be left with       2x-3+7x+14. You would then combine like terms and get 9x+11. To solve for x you would subtract 11 leaving you with 9x= -11. From there you would divide -11 by 9 and get x= -1.22.

Have a wonderful day!! :)

Answer:

a=25 b=100 c=17 d=68

Step-by-step explanation:

the test said so

Answer:

23

Step-by-step explanation:

Answer:

coefficient

Step-by-step explanation:

Answer:

$100 if you are trying to find the nearest hundreth.

Step-by-step explanation:

f(x) = [tex]\frac{2x + 7 - x^2}{4}[/tex]

f(2) just means we substitute 2 in for x.

f(2) = [tex]\frac{2(2) + 7 - (2)^2}{4}[/tex] = [tex]\frac{4 + 7 - 4}{4}[/tex] = [tex]\frac{7}{4}[/tex]

Answer: y =5(5)-3

5*5=25-3 =22  ANSWER IS y=22

Step-by-step explanation:

This is a geometric series, where the first term is -5 and the common ratio is -⅔.

aₙ = -5 (-⅔)ⁿ⁻¹

Answer:

i think it is -1/2

Answer:

[tex] -\dfrac{13}{18} [/tex]

Step-by-step explanation:

[tex] -\dfrac{8}{9} - (-\dfrac{1}{6}) = [/tex]

[tex] = -\dfrac{8}{9} + \dfrac{1}{6} [/tex]

[tex] = -\dfrac{16}{18} + \dfrac{3}{18} [/tex]

[tex] = -\dfrac{13}{18} [/tex]