please help marking brainlist

Answer:

1.25 g

Step-by-step explanation:

you start with 20g at 0 seconds.

divide by half after 2 seconds and you have 10g.

at 4 seconds you have 5g.

at 6 seconds you have 2.5g.

at 8 seconds you have 1.25g.

The size of the substance after 8 seconds will be 1.25 g

The mathematical expression combines numerical variables and operations denoted by addition, subtraction, multiplication, and division signs.

Mathematical symbols can be used to represent numbers (constants), variables, operations, functions, brackets, punctuation, and grouping. They can also denote the logical syntax's operation order and other properties.

Given that a radioactive substance has a half-life of 2 seconds. A scientist begins with a sample of 20 grams.

Start with 20g at 0 seconds and divide by half after 2 seconds and you have 10g.

4 seconds you have 5g.

6 seconds you have 2.5g.

8 seconds you have 1.25g.

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Answer:

i think it is 49:9

Step-by-step explanation:

because number going in 49:9 by which multiple it is 7x7 is 49 3x3 is 9 so the answer is 49:9

Answer:

28:12

Step-by-step explanation:

Multiply both 7 and 3 by 4 and you get the ratio 28:12.

Answer:

here the answer is 24

Step-by-step explanation:

answerrrrrerrr issss hereeeeeee

Answer:

0

Step-by-step explanation:

4 multiply by x(3) = 12

6 multiply by y(2) = 12

12 -12 =0

Answer:

Step-by-step explanation:

The Sydney Harbour Bridge is approximately 1200 metres long. A model of the bridge is built with a scale of 1:6000. What is the length of the model?

Pick one:

5cm

20cm

200cm

720cm

--------------------

scale = 1:6000

so

1200 : 6000 =  0.2m

0.2m = 20 cm

Answer:

20cm

Step-by-step explanation:

«A scale of 1:6000» means the model is smaller than the bridge by a factor of 6000. We can also make up a proportion [tex]\dfrac{1}{6000}=\dfrac{x}{1200}[/tex], where the left side is the scale, x is the model length, 1200 is the bridge length (in meters). So, finding x or just dividing 1200 by 6000, we get 0.2 meters. Provided 1 m = 100 cm, 0.2 m is 0.2 × 100 = 20 cm.

Answer:

24

Step-by-step explanation:

m=8x4 n=3x4 so that is the answer

Anwser 6720 ways different

Step-by-step explanation:

In this case, we must calculate the different ways using the permutation formula:

nPr = n! / (n - r)!

where n is the total number of people and r would come being the group of person that you want to put together the groups, therefore n = 8 and r = 5

replacing:

8P5 = 8! / (8 - 5)!

8P5 = 6720

That is to say that there are 6720 ways different winning groups are possible

Answer:

first put 2 in the numerator for the first blank and 2/9 in the second blank

Step-by-step explanation:

1/3 equals 3/9 and 3/9-1/9=2/9

Answer:

[tex]\frac{3}{9}[/tex]

Step-by-step explanation:

Answer:

No

Step-by-step explanation:

The answer is to find the sum of each number, because factors are pulling out from total numbers, but when multiplying you don't need to pull out anything so it would be number

Yep!!! Your correct

Answer:

3, 4, 5 and 5, 12, 13

Step-by-step explanation:

The square of the largest side is equal to the sum of the squares of the other 2 sides.

5² = 3² + 4²

13² = 5² + 12²

The 2 triplets are (3, 4, 5 ) and (5, 12, 13)

Answer:

Where's the Answer? There's No

Hello there!

Remember that equivalent fractions have the same value.

[tex]\frac{1}{2} , \frac{2}{24} ,\frac{3}{36}, \frac{4}{48}[/tex]

Hope this helps you!

~Just a felicitous girlie

#HaveASplendidDay

[tex]SilentNature :)[/tex]

Answer:

the nwser is 8 please mark brainliest

Step-by-step explanation:

Answer:

104

Step-by-step explanation:

Answer:

Move it to the right by 3 spaces.

Step-by-step explanation:

10^3 is 1000

On a number line the negative numbers are on the left and the positive numbers are on the right. So since the exponent is a positive 3 we move it to the right by 3 spaces to get 140

Answer:

the value of x is 12

......

Answer:

-5x+2

Step-by-step explanation:

1. Multiply number 2 and 2=4 so it is

4-5x-2

2. Combine like terms

-5x+4-2

3. Subtract the numbers

-5x+2

Answer:

x = -.1715 ≈ - .172    or x = -5.83

Step-by-step explanation:

x² + 6x + 1 = 0

x² + 6x = -1

Complete the square   Add to both sides (1/2 of the x-term, then square it.)

x² + 6x + 9  = -1 + 9

(x + 3)(x + 3) = 8

(x + 3)² = 8

[tex]\sqrt{(x + 3)^{2}[/tex]  = [tex]\sqrt{8}[/tex]

 x + 3 = ±  [tex]\sqrt{8}[/tex]

  x = -3 ± [tex]\sqrt{8}[/tex]

   x = -3 + [tex]\sqrt{8}[/tex]   or x = -3 - [tex]\sqrt{8}[/tex]

   x = -.1715 ≈ - .172    or x = -5.83

Answer:

The kinetic energy of the car is 43,200 Joules.

Step-by-step explanation:

KE = (1/2)mv^2

KE = (1/2)(600 kg)(12 m/s)^2

KE = (1/2)(600 kg)(144 m^2/s^2)

KE = 43,200 kg*m^2/s^2 = 43,200 Joules

Answer:

Step-by-step explanation:

KE= 1/2mv^2

KE = 1/2(600) 12^2

KE = 300 * 144 = 43200J

Step-by-step explanation:

f(x) = -3x - 8

f(-3) = -3(-3) - 8

f(-3) = 9 - 8

f(-3) = 1

Answer:

it would be 3 85

Step-by-step explanation:

but rounded would be 3 100 pls mark as brainliest

Answer:

705.3 repeated I don't know if that's what you want but

3 times of 705.33 and 2 subtracted is equal to 2114.

Simplification in mathematical terms is a process to convert a long mathematical expression in simple and easy form.

Given that,

2 less than 3 times a number equal to 2114.

Let the required number is x.

According to given condition,

3x - 2 = 2114

3x = 2114 + 2

3x = 2116

x = 2116 / 3

x = 705.33

The required number is 705.33.

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Answer:

(by using the first principle of differentiation)

We have the "Limit definition of Derivatives":

[tex]\boxed{\mathsf{f'(x)= \lim_{h \to 0} \{\frac{f(x+h)-f(x)}{h} \} ....(i)}}[/tex]

Here, f(x) = sec x, f(x+h) = sec (x+h)

[tex]\implies \mathsf{f'(x)= \lim_{h \to 0} \{\frac{sec(x+h)-sec(x)}{h} \} }[/tex]

[tex]\implies \mathsf{f'(x)= \lim_{h \to 0} \frac{1}{h} \{\frac{1}{cos(x+h)} -\frac{1}{cos(x)} \} }[/tex]

[tex]\implies \mathsf{f'(x)= \lim_{h \to 0} \frac{1}{h} \{\frac{cos(x)-cos(x+h)}{cos(x)cos(x+h)} \} }[/tex]

[tex]\boxed{\mathsf{cos\:A-cos\:B=-2sin(\frac{A+B}{2} )sin(\frac{A-B}{2} )}}[/tex]

=> cos(x) - cos(x+h) = -2sin{(x+x+h)/2}sin{(x-x-h)/2}

[tex]\implies \mathsf{f'(x)= \lim_{h \to 0} \frac{2sin(x+\frac{h}{2} )}{cos(x+h)cos(x)}\:.\: \lim_{h \to 0} \frac{sin(\frac{h}{2} )}{h} }[/tex]

[tex]\implies \mathsf{f'(x)= \lim_{h \to 0} \frac{sin(x+\frac{h}{2} )}{cos(x+h)cos(x)}\:.\: \lim_{h \to 0} \frac{2sin(\frac{h}{2} )}{h} }[/tex]

[tex]\implies \mathsf{f'(x)= \lim_{h \to 0} \frac{sin(x+\frac{h}{2} )}{cos(x+h)cos(x)}\:.\: \lim_{h \to 0} \frac{1\times sin(\frac{h}{2} )}{\frac{h}{2} } }[/tex]

[tex]\implies \mathsf{f'(x)= \lim_{h \to 0} \frac{sin(x+\frac{h}{2} )}{cos(x+h)cos(x)}\:.\: 1 }[/tex]

Substituting 0 for h and h/ 2

[tex]\implies \mathsf{f'(x)= \lim_{h \to 0} \frac{sin(x+0)}{cos(x+0)cos(x)} }[/tex]

[tex]\implies \mathsf{f'(x)= \lim_{h \to 0} \frac{sin(x)}{cos(x)cos(x)} }[/tex]

[tex]\implies \mathsf{f'(x)= \lim_{h \to 0} \frac{sin(x)}{cos(x)}\times \frac{1}{cos x} }[/tex]

[tex]\implies \mathsf{f'(x)= tan(x)\times sec(x) }[/tex]

Hence, we got

[tex]\underline{\mathsf{\overline{\frac{d}{dx} (sec(x))=sec(x)tan(x)}}}[/tex]

-  - - - -  - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

(by using other standard derivatives)

[tex] \boxed{ \mathsf{ \frac{d}{dx} ( \sec \: x) = \sec x \tan x }}[/tex]

We have a standard derivative for variables in x raised to an exponent:

[tex] \boxed{ \mathsf{ \frac{d}{dx}(x)^{n} = n(x)^{n - 1} }}[/tex]

Therefore,

[tex] \mathsf{ \frac{d}{dx}( \cos x)^{ - 1} = - 1( \cos \: x) ^{( - 1 - 1} } \\ \implies \mathsf{\ - 1( \cos \: x) ^{- 2 }}[/tex]

[tex] \implies \: \mathsf{ - \frac{1}{ (\cos x) {}^{2} } }[/tex]

The process of differentiating doesn't just end here. It follows chain mechanism, I.e.,

while calculating the derivative of a function that itself contains a function, the derivatives of all the inner functions are multiplied to that of the exterior to get to the final result.

[tex] \implies \mathsf{ - \frac{1}{ (\cos x )^{2} } \times ( - \sin x) }[/tex]

[tex] \implies \mathsf{ \frac{ \sin x }{ \cos x } \times ( \frac{1}{cos x} ) }[/tex]

[tex] \implies \mathsf{ \tan x \times \sec x }[/tex]

= sec x. tan x

Answer:

64%

Step-by-step explanation:

Step 1: Divide 16 by 25

Step 2: Multiply quotient by 100.

Therefore, 16/25 as a percentage is 64%.

Answer:

Well you can make a proportion

Percentage means ”Out of a hundred”

So you can make a proportion with any fraction Equal to x/100 since

X is the unknown perctange.

in this case it’s 16/25

16/25 = x/100

So cross multiply To solve for X

1600= 25x

x= 64

So 64 Percent

In this case you can use benchmarks. If you do it more or long enough, you’d memorize them.

In this case 25 is a bench mark of 1/4 or 25. 25 goes into 100 4 times so you can multiply 16 by 4 to get your percentage since if you do multiply 4, you have to do it to both the numerator and the Denominator.

so 16/25

16*4= 64

25*4=100

64/100 or 64 percent.

Common benchmarks for percentages

5, 10, 20, 25, 50

5 is always multiply by 20

10 is always multiply by 10

20 is always multiplied by 5

25 is always multiplied by 4

50 is always multiplied by 2

Answer:

4x - 12 = 84

Step-by-step explanation:

The last answer choice is correct because when you cross-multiply:

you get 4x - 12 = 84.

Therefore, the last option is correct.

Answer:

D would be the answer (4x-12=84)

Step-by-step explanation:

4/7=12/x-3

=>1/7=3/x-3

=>x-3=21

Multiplying both sides by 4

4(x-3)=4x21

=>4x-12=84

Hope this helped :)

Step-by-step explanation:

the second one (with the -5 as x values) is not a function, because the valid x value -5 has more than one associated different solution value y.

for a function a valid x value can lead only to exactly one result y value.

Answer:

The answer is C

Step-by-step explanation:

Hope that helps ;)

Answer:

[tex]\left \{ {{y=x; \ \ x\le 0} \atop {y=4+ \frac12x;\ \ x>0}} \right.[/tex]

Step-by-step explanation:

If you look at the graph you see that:

before 0, the graph has same y as it has x, or y=x.

after 0, the graph starts at 4, and increases by 1 every 2 steps horizontally, or has a slope of 1/2.

Finally, the 0 has to be included in the blue part of the graph based on where the solid dot is.

Step-by-step explanation:

5x - 6 = 3x + 2

5x - 3x = 2 + 6

2x = 8

x = 8/2

x = 4