# If x^2+y^2=25 and dy/dt=6, how do you find dx/dt when y=4 ?

There are two values depending on the point.

Don't use plagiarized sources. Get Your Custom Essay on
If x^2+y^2=25 and dy/dt=6, how do you find dx/dt when y=4 ?
Just from \$13/Page

##{dx}/{dt}={(-8 ” at ” (3,4)),(8 ” at “(-3,4)):}##

Let us look at some details.

First, let us find the values of ##x##.

By plugging in ##y=4## into ##x^2+y^2=25##,

##x^2+16=25 Rightarrow x^2=9 Rightarrow x=pm3##

Now, let us find some derivatives.

By differentiating with respect to ##t##,

##d/{dt}(x^2+y^2)=d/{dt}(25) Rightarrow 2x{dx}/{dt}+2y{dy}/{dt}=0##

by dividing by ##2x##,

##Rightarrow {dx}/{dx}+y/x{dy}/{dt}=0##

by subtracting ##y/x{dy}/{dt}##,

##Rightarrow {dx}/{dt}=-y/x{dy}/{dt}##

Since ##y=4##, ##x=pm3##, and ##{dy}/{dt}=6##,

##{dx}/{dt}=-{4}/{pm3}(6)=pm8##

## Calculate the price of your order

550 words
We'll send you the first draft for approval by September 11, 2018 at 10:52 AM
Total price:
\$26
The price is based on these factors:
Number of pages
Urgency
Basic features
• Free title page and bibliography
• Unlimited revisions
• Plagiarism-free guarantee
• Money-back guarantee
On-demand options
• Writer’s samples
• Part-by-part delivery
• Overnight delivery
• Copies of used sources
Paper format
• 275 words per page
• 12 pt Arial/Times New Roman
• Double line spacing
• Any citation style (APA, MLA, Chicago/Turabian, Harvard)

# Our guarantees

Delivering a high-quality product at a reasonable price is not enough anymore.
That’s why we have developed 5 beneficial guarantees that will make your experience with our service enjoyable, easy, and safe.

### Money-back guarantee

You have to be 100% sure of the quality of your product to give a money-back guarantee. This describes us perfectly. Make sure that this guarantee is totally transparent.

### Zero-plagiarism guarantee

Each paper is composed from scratch, according to your instructions. It is then checked by our plagiarism-detection software. There is no gap where plagiarism could squeeze in.

### Free-revision policy

Thanks to our free revisions, there is no way for you to be unsatisfied. We will work on your paper until you are completely happy with the result.