All categories

3 years ago

I need help ASAP on number 8 b and c. Thank you

Mathematics

1 answer:

s344n2d4d5 [400]3 years ago

6 0

I think you're having trouble because the equation you wrote for 8a has a slight typo.

The question says that the length is 9 less than twice the width. Your equation states the length is 9 times the width minus 2. So the length actually equals 2w – 9, meaning that w(2w – 9) = 180

Hope this helps! If you're still having trouble, let me know :)

You might be interested in

Suppose you purchase a $1000 bond with a 4% coupon. What is the periodic

m_a_m_a [10]

Answer:

Step-by-step explanation:

5 0

3 years ago

Mike wants to conduct a survey to find how much time the students of his school spent watching television. Which of the followin

Allisa [31]

Answer:

How many hours per week do you watch television?

Step-by-step explanation:

In order to conduct a proper survey about a specific topic, it is necessary to be direct and clear. In the case of time spent by students watching TV, asking this question would be effective enought to collect necessary data so as to provide useful and good quality information, which will result in a sucessful survey.

3 0

3 years ago

A Bernoulli differential equation is one of the form dxdy+P(x)y=Q(x)yn Observe that, if n=0 or 1, the Bernoulli equation is line

aleksandr82 [10.1K]

It's unclear whether the ODE is

$xy'+y=4xy^2$

$xy+y'=4xy^2$

If the first case, then divide through both sides by $y^2$ to get

$xy^{-2}y'+y^{-1}=4x$

then substitute $z=y^{-1}$ , so that $z'=-y^{-2}y'$ . Then

$-xz'+z=4x\implies-\dfrac1xz'+\dfrac1{x^2}z=\left(-\dfrac1xz\right)'=\dfrac4x$

$\implies-\dfrac1xz=\displaystyle\int\frac4x\,\mathrm dx$

$\implies z=-4x\ln|x|+Cx$

$\implies\boxed{y=\dfrac1{Cx-4x\ln|x|}}$

If the second, then dividing through by $y^2$ gives

$xy^{-1}+y^{-2}y'=4x$

The same substitution as before gives

$xz-z'=4x\implies e^{-x^2/2}z'-xe^{-x^2/2}z=\left(e^{-x^2/2}z\right)'=-4xe^{-x^2/2}$

$\implies e^{-x^2/2}z=\displaystyle-4\int xe^{-x^2/2}\,\mathrm dx$

$\implies z=4+Ce^{x^2/2}$

$\implies\boxed{y=\dfrac1{4+Ce^{x^2/2}}}$

5 0

3 years ago

Sanjay and his friends are doing a physics lab on air pressure. First, they fill a balloon with air until it reaches a pressure

KatRina [158]

Answer: After 8 hours the pressure will be at -60?

Explanation: not sure how the balloon can reach -60 kilopascals but 15% of 300 is 45 and 45 x 8(hours) is 360. 300 - 360 is -60

4 0

3 years ago

-6x + 9y = -21<br> -2x-4y=14

ankoles [38]

Simple....

work is attached. :D

7 0

3 years ago