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2 years ago

Will someone help with this ! I was allowed a retry for it and I don’t know how to do it

Mathematics

1 answer:

pashok25 [27]2 years ago

6 0

Answer:

$\frac{dN}{dt}=k(725-N)\\separating the variables and integrating\\\int \frac{dN}{725-N}=\int kdt+c\\-log (725-N)=kt+c\\log (725-N)=-kt-c\\(725-N)=e^{-kt-c} =e^{-kt} *e^{-c} =Ce^{-kt} \\when t=0,N=400\\725-400=Ce^{0} =C\\C=325\\when t=3,N=650\\725-650=325e^{-3k} \\\frac{75}{325}=(e^{-k})^3\\\\e^{-k} =(\frac{3}{13}) ^{\frac{1}{3} } \\when t=5\\725-N=325(\frac{3}{13}) ^{\frac{5}{3} } =325*\frac{3}{13}*(\frac{3}{13} )^{\frac{2}{3}}\\N=725-75*(\frac{3}{13} )^{\frac{2}{3} }=725-28=697$

Step-by-step explanation:

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Find the missing coefficient. (5d − 7)(5d − 6) = 25d2 ++ 42 5 65 –5 –65

andrew11 [14]

I do believe it is -65d because the equation will look like this in the end
-65d=-65d.

3 0

2 years ago

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Jeff and George each have a box of popcorn. Whose box holds more popcorn? Choose 1 answer: Choose 1 answer: (Choice A, Checked)

serg [7]

Answer:

Jeff's Popcorn 130^3

Step-by-step explanation

(Jeff's 130^3) .

First 20.5*10^2 which is 20.5*100 which equals 2050.

Then find the volume for the other box of popcorn.

30*8^2 which is 1920.

subtract 2050 by 1920 and you get 130.

8 0

3 years ago

Read 2 more answers

Somebody please help me

jolli1 [7]

Answer:

A). Scale factor = $\frac{1}{4}$

B). Length of the unknown side = 2.75 feet

Step-by-step explanation:

Part A

Since, the large rectangle was scaled by a scale factor 'k' to form the smaller rectangle,

Scale factor = $\frac{\text{Side length of the image}}{\text{Side length of the preimage}}$

= $\frac{\text{Side length of the smaller rectangle}}{\text{Side length of the larger rectangle}}$

= $\frac{4}{16}$

= $\frac{1}{4}$

Part B

Scale factor = $\frac{\text{Side length of the smaller rectangle}}{\text{Side length of the larger rectangle}}$

$\frac{1}{4}=\frac{\text{Side length of the smaller rectangle}}{11}$

Therefore, side length of the unknown side = $\frac{11}{4}$ = 2.75 feet

8 0

2 years ago

Please answer with explanation, I don't understand.<br><br> <img src="https://tex.z-dn.net/?f=%5Csqrt%7Bx%5E2-14x%2B49%7D%20%3Dx

Crank

Answer: x ≥ 7

Step-by-step explanation:

You have to square both sides of the equation. You can manipulate an equation or function any way imaginable as long as it is done equally and helps the problem become easier. If we square this, the radical will cancel and we will get two trinomials equal to each other.

$x^2-14x+49=(x-7)^2\\x^2-14x+49=x^2-14x+49$

We can see the two expressions are exactly equal to each other. All real numbers are solutions, besides a few. These few are when the radical is equal to a negative number. So lets set up an inequality stating that the radical must be greater than or equal to 0.

$x^2-14x+49\geq 0\\(x-7)^2 \geq 0\\x \geq 7$

6 0

2 years ago

I need you to answer with a, b, c, d

solong [7]

To find the zeros of a quadratic fiunction given the equation you can use the next quadratic formula after equal the function to 0:

$\begin{gathered} ax^2+bx+c=0 \\ \\ x=\frac{-b\pm\sqrt[]{b^2-4ac}}{2a} \end{gathered}$

For the given function:

$f(x)=2x^2-10x-3$ $x=\frac{-(-10)\pm\sqrt[]{(-10)^2-4(2)(-3)}}{2(2)}$ $x=\frac{10\pm\sqrt[]{100+24}}{4}$ $\begin{gathered} x=\frac{10\pm\sqrt[]{124}}{4} \\ \\ x=\frac{10\pm\sqrt[]{2\cdot2\cdot31}}{4} \\ \\ x=\frac{10\pm\sqrt[]{2^2\cdot31}}{4} \\ \\ x=\frac{10\pm2\sqrt[]{31}}{4} \\ \end{gathered}$ $\begin{gathered} x_1=\frac{10}{4}+\frac{2\sqrt[]{31}}{4} \\ \\ x_1=\frac{5}{2}+\frac{\sqrt[]{31}}{2} \end{gathered}$ $\begin{gathered} x_2=\frac{10}{4}-\frac{2\sqrt[]{31}}{4} \\ \\ x_2=\frac{5}{2}-\frac{\sqrt[]{31}}{2} \end{gathered}$

Then, the zeros of the given quadratic function are:

$\begin{gathered} x=\frac{5}{2}+\frac{\sqrt[]{31}}{2} \\ \\ x_{}=\frac{5}{2}-\frac{\sqrt[]{31}}{2} \end{gathered}$

Answer: Third option

8 0

1 year ago