I will give brainliest!! please help!!!

The number of bacteria in a certain culture doubled every hour. If there were 30 bacteria present in the culture initially, how

vichka [17]

Answer:

The number of bacteria after $8th$ will be $3840$

Step-by-step explanation:

Given the initially 30 bacteria present in the culture.

Also, the number of bacteria got doubled every hour.

So, using the equation

$A=A_0r^{n-1}$

Where $A$ is number of bacteria after $n$ hours.

$A_0$ is bacteria present initially.

$r$ is the common ration, in our problem it is given that bacteria doubles every hour. So, $r=2$

And $n$ is the number of hours. In our problem we need amount of bacteria at the end of $8th$ hours. So, $n=8$

Plugging values in the formula we get,

$A=30(2)^{8-1}\\A=30\times 2^7\\A=30\times 128\\A=3840$

So, number of bacteria after $8th$ will be $3840$

3 0

3 years ago

The middle side of a triangle is half of 3 times the length of the shortest side. The longest side is 2 centimeters longer than

USPshnik [31]

Answer:

The difference between the longest and shortest sides of the triangle is 4 cm.

Explanation:

Step Number One:

Let the shortest side of the triangle have a length of x.

The middle side of the triangle has a length that is half of 3 times the length of the shortest side. This can be written as 1/2*3x, which equals 3/2x.

The longest side of the triangle has a length that is 2 centimeters longer than the length of the middle side. This can be written as 3/2x + 2.

Step Number Two:

The perimeter of the triangle, which can be found by adding the lengths of all of the sides of the triangle, is 18 centimeters. This can be shown by the following equations:

Shortest Side + Middle Side + Longest Side = Perimeter

x + 3/2x + 3/2x + 2 = 18

4x + 2 = 18

4x = 16

x = 16/4

x = 4

Step Number Three:

This means that the shortest side of the triangle has a length of 4 centimeters and the longest side of the triangle has a length of 8 centimeters.

8 cm - 4 cm = 4 cm

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Are you still confused? Not feeling confident in your ability to solve these types of problems? Some helpful topics to practice are listed below!

Still confused on ...

Step 1 - Practice equation solving!

Step 2 - Practice perimeter!

Step 3 - Practice addition and subtraction!

Remember: Certain problems may be tricky, but practice makes perfect!

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Answer by Math_Is_Me_123

7 0

3 years ago

The width of a rectangle is 18 meters less than twice the length, x. The width of the rectangle is 68 meters. Which equation can

Morgarella [4.7K]

Answer:

None of the options are correct, as the answer is 2x - 18 = 68.

Step-by-step explanation:

The 2x represents the length (x) being half of the width (68)

The -18 represents the width (68) being 18 less than twice the length (2x)

8 0

3 years ago

What is the y value of the vertex of the function f(x)=-(x-3)(x+11)

AnnyKZ [126]

Answer:

49

Step-by-step explanation:

Because there is a minus sign infront of x-3, we can convert x-3 into the negative form:

- * x

- * -3

-x + 3

Which gives us:

(-x + 3)(x + 11)

Now expand the brackets with the formula:

(a + b)(c + d) = ac + ad + bc + bd

-x * x = -x²

-x * 11 = -11x

3 * x = 3x

3 * 11 = 33

-x² - 11x + 3x + 33

-x² - 8x + 33

The formula for finding the x coordinate of a vertex in a quadratic equation is:

x = $\frac{-b}{2a}$

Plug known variables in:

$x = \frac{-(-8)}{2(-1)}$

$x = \frac{8}{-2}$

$x = -4$

Now, to find the y coordinate, plug this variable back into the quadratic equation:

-x² - 8x + 33

$y = -(-4^2) - (32) + 33\\y = -16 + 32 + 33\\\\$

y = 49

So the y coordinate of the vertex is 49.

Hope this helps!

4 0

3 years ago

2 meters 2 meters 5 meters 4 meters What is the area of the shape?

Alex73 [517]

C
A million apologies if I’m incorrect

6 0

3 years ago

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