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3 years ago

15

(1 point) In this problem we consider an equation in differential form M dx + N dy = 0. (8x + 8y)dx + (8x + 4y)dy = 0 Find My =

8 Nx = 8 If the problem is exact find a function F(x, y) whose differential, dF(x, y) is the left hand side of the differential equation. That is, level curves F(x, y) = C, give implicit general solutions to the differential equation. If the equation is not exact, enter NE otherwise find F(x, y) (note you are not asked to enter C) F(x, y) =

1 answer:

OLga [1]3 years ago

3 0

The ODE is exact because $M_y=N_x$ . Then

$F_x=8x+8y\implies F(x,y)=4x^2+8xy+g(y)$

$F_y=8x+g'(y)=8x+4y\implies g'(y)=4y\implies g(y)=2y^2+C$

So we have

$F(x,y)=4x^2+8xy+2y^2=C$

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A cook has 6 and 1/2 cup of sliced carrots how many 3/4 cup servings of carrots is this

aalyn [17]

Answer:

8 and 2/3

Step-by-step explanation:

Divide 6.5 by 0.75 and you get $26/3$ , or 8 and 2/3

5 0

3 years ago

How do you solve this?

puteri [66]

Answer:

Width: 7

Length: 14

Step-by-step explanation:

The area of a rectangle can be found my multiplying the length by the width. We do not know neither the length nor the width. However, we do know that the length is 7 feet longer than the width. Because we do not know the value of either side, let's let $x$ represent the width.

Since the length is 7 feet longer, we can represent the length by $x+7$ .

Now that we have our values for the length and the width we can multiply them together to find our area.

$(x)(x+7)=x^{2} +7x$

Now we have our equation, so we can address the changes made by the original question. The original question states that when 7 is added to both the length and width the area becomes 3 times larger. To do so simply increase each side by 7 by adding 7 to the original values.

$(x+7)(x+14)$

And multiply our area by 3.

$3(x^{2} +7x)$

set these equal to each other to find your new equation.

$(x+7)(x+14)=3(x^{2} +7x)$

Now you need to solve for $x$ . To do this first muliply $(x+7)$ and $(x+14)$ .

$(x+7)(x+14)=\\x^{2} +14x+7x+98=\\x^{2} +21x+98$

Then multiply $3(x^{2} +7x)$

$3(x^{2} +7x)=\\3x^{2} +21x$

Now you can begin solving for $x$ .

$x^{2} +21x+98=3x^{2} +21x$

Subtract $x^{2}$ from both sides.

$21x+98=2x^{2} +21x$

Subtract $21x$ from both sides.

$98=2x^{2}$

Divide by 2.

$49=x^{2}$

And finally take the sqaure root of both sides.

$\sqrt{x^{2} }=\sqrt{49}\\x=7$

Remember, because we are dealing with length, there cannot be negative. So while normally we would get both +7 <em>and</em> -7, in this case we <em>only </em>get +7.

Now that we have the value of $x$ , we can plug it into our original values.

For width we simply get 7.

For length we get 7+7=14

To check our answer we cna multiply 7 by 14 to get 98. Then we can add 7 to our length and width to get 14 and 21. Multiply these together and we get 294. 294 divided by 3 is 98, proving our answer correct.

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3 years ago

Does this graph represent a function? Why

Sladkaya [172]

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1 year ago

If k is non zero digit for which base of k is the sum, 1+kk=100 true?

Anna007 [38]

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3 years ago

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Allushta [10]

Answer:

It would be D because you are timing 2 by a number which would have n together

Hope this helped

3 0

3 years ago