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2 years ago

X + 5y =100 x +y = 60 Which ordered pair is the solution of the system?

Mathematics

1 answer:

Simora [160]2 years ago

4 0

Answer:

lets start with the easy equation. X+Y=60. so we take 60 and subtract Y to get X by itself. meaning X = 60-Y. every time we see X replace with (60-Y).

X + 5Y = 100 change to

60-Y+5Y = 100

5Y - Y = 4y.

60+4Y = 100. 100 minus the 60 = 40. 4Y=40. divide by 4. Y = 10. ok so now we solve for X. X + Y (or 10) = 60. 60-10 = 50. X = 50.

Step-by-step explanation:

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Given mſn, find the value of x.<br> (6x-7)º<br> m<br> (4x-10°

Pavel [41]

Answer:

x = 3

Step-by-step explanation:

These angles are actually equal to each other

This is because when two lines intersect, the two opposite angles are the same.

Since they are the same, you can set them equal to each other

Like so:

6x - 7 = 4x - 1

Then solve:

6x - 7 = 4x - 1

6x = 4x +6

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5 0

1 year ago

Problem 10: A tank initially contains a solution of 10 pounds of salt in 60 gallons of water. Water with 1/2 pound of salt per g

AysviL [449]

Answer:

The quantity of salt at time t is $m_{salt} = (60)\cdot (30 - 29.833\cdot e^{-\frac{t}{10} })$ , where t is measured in minutes.

Step-by-step explanation:

The law of mass conservation for control volume indicates that:

$\dot m_{in} - \dot m_{out} = \left(\frac{dm}{dt} \right)_{CV}$

Where mass flow is the product of salt concentration and water volume flow.

The model of the tank according to the statement is:

$(0.5\,\frac{pd}{gal} )\cdot \left(6\,\frac{gal}{min} \right) - c\cdot \left(6\,\frac{gal}{min} \right) = V\cdot \frac{dc}{dt}$

Where:

$c$ - The salt concentration in the tank, as well at the exit of the tank, measured in $\frac{pd}{gal}$ .

$\frac{dc}{dt}$ - Concentration rate of change in the tank, measured in $\frac{pd}{min}$ .

$V$ - Volume of the tank, measured in gallons.

The following first-order linear non-homogeneous differential equation is found:

$V \cdot \frac{dc}{dt} + 6\cdot c = 3$

$60\cdot \frac{dc}{dt} + 6\cdot c = 3$

$\frac{dc}{dt} + \frac{1}{10}\cdot c = 3$

This equation is solved as follows:

$e^{\frac{t}{10} }\cdot \left(\frac{dc}{dt} +\frac{1}{10} \cdot c \right) = 3 \cdot e^{\frac{t}{10} }$

$\frac{d}{dt}\left(e^{\frac{t}{10}}\cdot c\right) = 3\cdot e^{\frac{t}{10} }$

$e^{\frac{t}{10} }\cdot c = 3 \cdot \int {e^{\frac{t}{10} }} \, dt$

$e^{\frac{t}{10} }\cdot c = 30\cdot e^{\frac{t}{10} } + C$

$c = 30 + C\cdot e^{-\frac{t}{10} }$

The initial concentration in the tank is:

$c_{o} = \frac{10\,pd}{60\,gal}$

$c_{o} = 0.167\,\frac{pd}{gal}$

Now, the integration constant is:

$0.167 = 30 + C$

$C = -29.833$

The solution of the differential equation is:

$c(t) = 30 - 29.833\cdot e^{-\frac{t}{10} }$

Now, the quantity of salt at time t is:

$m_{salt} = V_{tank}\cdot c(t)$

$m_{salt} = (60)\cdot (30 - 29.833\cdot e^{-\frac{t}{10} })$

Where t is measured in minutes.

7 0

2 years ago

Old faithful in Yellowstone National Park shoots water 60 feet into the air that casts a shadow of 42 feet. What is the height o

Serhud [2]

Answer:

The height of near by tree will be 90 feet.

Step-by-step explanation:

Considering the water triangle as shown in figure a.

As the old faithful shoots water 60 feet into the air that casts a shadow of 42 feet.

Considering the tree triangle as shown in figure a. The tree triangle has a shadow 63 feet long.

Let x be the height of near by tree that cost a shadow 63 feet long.

Assuming that the triangles are similar

So,

the ratios of similar triangles will be related as:

$\frac{63}{42}=\frac{x}{60}$

$\mathrm{Switch\:sides}$

$\frac{x}{60}=\frac{63}{42}$

${x}=60.\frac{63}{42}$

$x=90$ feet

Therefore, the height of near by tree will be 90 feet.

Keywords: ratio, similar triangle

Learn more about similar triangle from brainly.com/question/10161974

#learnwithBrainly

7 0

2 years ago

Pls help i will give brainliest

Novosadov [1.4K]

<h3>Answer: -a > -b</h3>

Explanation:

Let's go over an example.

We'll have a = 1 and b = 7 which makes a < b true. Feel free to pick your own favorite pair of numbers such that b is larger than 'a'.

The corresponding opposites are: -a = -1 and -b = -7

The relationship flips because the opposites of each number are flipped. So instead of saying -a < -b, we have -a > -b

Sure enough, -1 > -7 is a true statement. Use a number line to see this. I recommend a vertical number line.

In short, going from a < b to -a > -b means we flip the signs of each term, and we flip the inequality sign as well.

4 0

1 year ago

Write two subtraction facts related to 7 + 5 =12

Nezavi [6.7K]

Answer:

12-5=7

12-7=5

Step-by-step explanation:

5 0

2 years ago