Can someone help me please!

For the system of the equation given we have proven that b = -1.

Given that,
a - 2b = 8
4a + 3b = 21
To prove b= -1

The equation is the relationship between variables and is represented as y =ax +b is an example of a polynomial equation.

The process in mathematics to operate and interpret the function to make the function or expression simple or more understandable is called simplifying and the process is called simplification.

Here,
a - 2b = 8  - - - - - - - (1)
4a + 3b= 21 - - - -- - - (2)
From equation 1
a = 8 + 2b
put a in equation 2
4 (8 + 2b) + 3b = 21
32 + 8b + 3b = 21
11b = 21 - 32
11b = -11
b = -1
Hence proved.

Thus, for the system of the equation given, we have proven that b = -1.

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Answer:

the 2 one is better because you get more pens

Step-by-step explanation:

you get more pens

Answer:

7 hope this helps

Step-by-step explanation:

9 - 5 = 4 + 3 = 7

Answer:

They will have the same population after 6 hours

Step-by-step explanation:

The general exponential equation format for this is;

P = P_o(e^(kt))

For Culture A, we are told that it had an initial population of 200 and doubles every hour.

Thus;

After 1 hour, P = 400

After 2 hours, P = 800

After 3 hours, P = 1600

Thus;

At t = 1, we have;

400 = 200(e^(k × 1))

400/200 = e^(k)

e^(k) = 2 - - - (eq 1)

At t = 2, we have;

800 = 200(e^(k × 2))

800/200 = e^(2k)

e^(2k) = 4 - - - (eq 2)

To find k, let's divide eq 1 by eq 2.

(e^(2k))/e^(k) = 4/2

e^(2k - k) = 2

e^(k) = 2

k = In 2

k = 0.6931

Thus;

P = 200e^(0.6931t)

For Culture B, we are told that it had an initial population of 819200 but has been contaminated. Its population is now decreasing by half every hour.

Thus;

After 1 hour, P = 409600

After 2 hours, P = 204800

After 3 hours, P = 102400

Thus;

At t = 1, we have;

409600 = 819200(e^(k × 1))

409600/819200 = e^(k)

e^(k) = 0.5 - - - (eq 1)

At t = 2, we have;

204800 = 819200(e^(k × 2))

204800/819200 = e^(2k)

e^(2k) = 0.25 - - - (eq 2)

To find k, let's divide eq 1 by eq 2.

(e^(2k))/e^(k) = 0.25/0.5

e^(k) = 0.5

k = In 0.5

k = -0.6931

Thus;

P = 819200(e^(-0.6931t))

We want to find the time when the 2 cultures will have the same population. Thus;

200e^(0.6931t) = 819200(e^(-0.6931t))

Arranging, we have;

(e^(0.6931t))/(e^(-0.6931t)) = 819200/200

e^(0.6931t - (-0.6931t) = 4096

e^(1.3862t) = 4096

1.3862t = In 4096

1.3862t = 8.3178

t = 8.3178/1.3862

t ≈ 6 hours

Answer:

Length of the ladder = 9.5 feet

Step-by-step explanation:

Point A of ladder AC is at 9 ft from the ground and point C is 3 feet from the base of the wall,

AB = 9 feet

BC = 3 feet

By applying Pythagoras theorem in the right triangle,

AC² = AB² + BC²

AC² = 9² + 3²

AC² = 81 + 9

AC = √90

     = 9.486 feet

     ≈ 9.5 feet

Therefore, length of the ladder is 9.5 feet.

Answer:

m = -12

Step-by-step explanation:

Formula:

m = (y2 - y1) / (x2 - x1) => plug in points

(4,-5) and (3,7)

Answer:

[tex]\sqrt{13}[/tex]

The rate of change of distance between two cars at the given time is required.

The required rate of change is [tex]\sqrt{13}[/tex] feet/s

a = Distance covered in 5 s by bike A = [tex]2\times 5=10\ \text{feet}[/tex]

b = Distance covered in 5 s by bike B = [tex]3\times 5=15\ \text{feet}[/tex]

c = Distance between A and B in 5 s = [tex]\sqrt{10^2+15^2}=5\sqrt{13}\ \text{feet}[/tex]

Applying Pythagoras theorem

[tex]a^2+b^2=c^2[/tex]

Differentiating with respect to time

[tex]2a\dfrac{da}{dt}+2b\dfrac{db}{dt}=2c\dfrac{dc}{dt}\\\Rightarrow \dfrac{dc}{dt}=\dfrac{a\dfrac{da}{dt}+b\dfrac{db}{dt}}{c}\\\Rightarrow \dfrac{dc}{dt}=\dfrac{10\times 2+15\times 3}{5\sqrt{13}}\\\Rightarrow \dfrac{dc}{dt}=\sqrt{13}\ \text{feet/s}[/tex]

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Therefore, when we draw the slope of line then the slope of corresponding line segment in the preimage and image apply about the line segments both are equal.

What is the slope of line?

The slope of a line is its vertical change divided by its horizontal change, also known as rise over run.

When the two or more line segments that have the same slope are parallel to each other.So, the lines graphed by a system of equation is also same slope which would be parallel to each other.

Hence, when we draw the slope of line then the slope of corresponding line segment in the preimage and image apply about the line segments both are equal.

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Answer:

cool, but what is the question?

9514 1404 393

Answer:

  325 cm³

Step-by-step explanation:

The volume is the product of the dimensions shown.

  V = LWH

  V = (13 cm)(5 cm)(5 cm) = 325 cm³

r= 18/1+b

B= -1 + 18/r

Answer: 1 : 2 : 2

Step-by-step explanation:

2 : 4 : 2 divided by 2 is 1 : 2 : 2 so they're equivalent.

Answer:

Step-by-step explanation:

it’s B,C,D

Answer:

probs c

Step-by-step explanation:

c bc 3x>21 is x>7

the smallest whole number out of the multiple choice answer that fits into the solution is 8

Answer:

C. 8

Step-by-step explanation:

To answer you must first solve the inequality, do this by dividing both sides by 3. [tex]\frac{3x}{3} > \frac{21}{3}[/tex], which simplifies to x > 7. This means that x must be greater than 7 without being 7 because the inequality does not use the "or equal to" sign. Therefore, 8 must be the correct answer because it is the smallest whole number that is larger than 7.

Answer: The X intercepts are 5 and -3/2

Answer:

y = -3/5x + 1.3

Step-by-step explanation:

y = mx + b

m: slope

b: y-intercept

First, let's substitute in the values.

Point: (2, 1)

Slope: -3/5

y = mx + b

(1) = (-3/5)(2) + b

1 = -0.3 + b

1 + 0.3 = -0.3 + b + 0.3

b = 1.3

Now, let's add the slope and y-intercept to the equation.

y = mx + b

m = -3/5

b = 1.3

y = -3/5x + 1.3

Hope this helped! <3

Answer:

25 ft

Step-by-step explanation:

Got it right on EDG2020

The ball will reach the maximum height in a second. Then the maximum height the ball reaches will be 25 ft.

The rate of change of a function with respect to the variable is called differentiation. It can be increasing or decreasing.

Lori tosses a ball into the air. The equation models the height, y, in feet, of the ball after x seconds.

[tex]\rm y = -16(x - 1)^2 + 25[/tex]

Differentiate the equation with respect to x, then we have

[tex]\begin{aligned} y' &= 0\\\\\dfrac{d}{dx}[-16(x - 1)^2 + 25] &= 0\\\\ -32(x-1) &= 0\\\\x &= 1 \end{aligned}[/tex]

Then the maximum height the ball reaches will be

[tex]\rm y = -16(1 - 1)^2 + 25\\\\y = -16*0^2 + 25\\\\y = 25[/tex]

Then the maximum height the ball reaches will be 25 ft.

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Answer:

Was number 11

Step-by-step explanation:

50 - 6 = 44

44 dividid 4 is 11

Answer:

Quotient: 2

Remainder: 0

50 = 25 × 2 + 0

Step-by-step explanation:

Answer:0.516

Step-by-step explanation:You need to divide 29.25 by 50.25.

Answer:

D

Step-by-step explanation:

Just took the quiz

The confidence interval that  would produce the widest interval when estimating the mean of a population should be 83%.

It refers to the range of values where the sample should be watched also in this the value should be determined that correctly represent the population.

Also, the more the confidence interval the more should be the widest interval.

Therefore, the last option is correct.

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Answer:

Slope = -4

Step-by-step explanation:

The slope is negative because the line is going down.

The line goes down 4 times and goes right once = 4

The required slope of the given graph would be - 4 which is a negative slope.

A graph can be defined as a pictorial representation or a diagram that represents data or values.

The graph is given in the question

Each square on a grid represents one unit on each side.

We have to determine the slope of the given graph D

According to the given graph, we take two points (4, 12) and (7, 0)

The slope of a line is defined as the gradient of the line.

It is denoted by m

Slope m = (y₂ - y₁)/(x₂ -x₁ )

Consider two points on a line—Point 1 and Point 2. Point 1 has coordinates (x₁,y₁) and Point 2 has coordinates (x₂, y₂)

Slope m = (0 - 12)/(7 -3 )

Slope m = -12/3

Slope m = -4

Thus, the required slope of the given graph would be - 4

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Answer:

Step-by-step explanation:

for this problem u need the unit circle.

In the unit circle there is a point with -1/2 as the x value that is at 240 degrees.

then you convert 240 degrees to radians --> 240 X pi/180 = 4.189

the unit circle is below, you needa remember for the test

Good luck on your EOC, i'm doing it too

Answer:

x = 0

Step-by-step explanation:

Let's divid both sides of the equation by 2 first, so we don't have as much work to do in the next step:

[tex]4x-2y=6\\2x-y=3[/tex]

Substituting -3 for y:

[tex]2x-(-3)=3\\2x+3=3\\2x=0\\x=0[/tex]

Answer:

The slope is 6/1 or 6

Step-by-step explanation:

Answer:

plz give me BRAINLIEST

Step-by-step explanation:

c. p >-13

Answer:

because of vertical angles, 108

Step-by-step explanation:

Answer:

108 degrees

Step-by-step explanation:

Opposite angles are equal.

Thus, x = 108 degrees.

Answer:

34+15y

Step-by-step explanation:

Let x players want a sweatshirt and y players want sweatpants.

Each sweatshirt costs ​$34 and each pair of sweatpants costs ​$15.

Cost of sweatshirt = 34x

Cost of sweatpants = 15y

Total cost = cost of sweatshirt + cost of sweatpants

= 34x+15y

Hence, the total cost is "34x+15y".

Answer:

cross multiplication

Step-by-step explanation:

1 5n

_ _

_