Solve proportion for x 3/2x+5 = 1/9x A. 1/5 B. 1/2 C.5/3 D.16/5

PLEASE HELP L has y-intercept (0,5) and is perpendicular to the line with equation y=1/3x+1

marin [14]

Answer:

y=-3x+5

Explanation:

Given a line L such that:

• L has y-intercept (0,5); and

,

• L is perpendicular to the line with equation y=(1/3)x+1.

We want to find the equation of the line in the slope-intercept form.

The slope-intercept form of the equation of a straight line is given as:

$\begin{equation} y=mx+b\text{ where }\begin{cases}m={slope} \\ b={y-intercept}\end{cases} \end{equation}$

Comparing the given line with the form above:

$y=\frac{1}{3}x+1\implies Slope,m=\frac{1}{3}$

Next, we find the slope of the perpendicular line L.

• Two lines are perpendicular if the product of their slopes is -1.

Let the slope of L = m1.

Since L and y=(1/3)x+1 are perpendicular, therefore:

$\begin{gathered} m_1\times\frac{1}{3}=-1 \\ \implies Slope\text{ of line L}=-3 \end{gathered}$

The y-intercept of L is at (0,5), therefore:

$y-intercept,b=5$

Substitute the slope, m=-3, and y-intercept, b=5 into the slope-intercept form.

$\begin{gathered} y=mx+b \\ y=-3x+5 \end{gathered}$

The equation of line L is:

$y=-3x+5$

7 0

11 months ago

This is a "water tank" calculus problem that I've been working on and I would really appreciate it if someone could look at my w

Sedaia [141]

Part A

Everything looks good but line 4. You need to put all of the "2h" in parenthesis so the teacher will know you are squaring all of 2h. As you have it right now, you are saying "only square the h, not the 2". Be careful as silly mistakes like this will often cost you points.

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Part B

It looks like you have the right answer. Though you'll need to use parenthesis to ensure that all of "75t/(2pi)" is under the cube root. I'm assuming you made a typo or forgot to put the parenthesis.

dh/dt = (25)/(2pi*h^2)
2pi*h^2*dh = 25*dt
int[ 2pi*h^2*dh ] = int[ 25*dt ] ... applying integral to both sides
(2/3)pi*h^3 = 25t + C
2pi*h^3 = 3(25t + C)
h^3 = (3(25t + C))/(2pi)
h^3 = (75t + 3C)/(2pi)
h^3 = (75t + C)/(2pi)
h = [ (75t + C)/(2pi) ]^(1/3)

Plug in the initial conditions. If the volume is V = 0 then the height is h = 0 at time t = 0
0 = [ (75(0) + C)/(2pi) ]^(1/3)
0 = [ (0 + C)/(2pi) ]^(1/3)
0 = [ (C)/(2pi) ]^(1/3)
0^3 = (C)/(2pi)
0 = C/(2pi)
C/(2pi) = 0
C = 0*2pi
C = 0

Therefore the h(t) function is...
h(t) = [ (75t + C)/(2pi) ]^(1/3)
h(t) = [ (75t + 0)/(2pi) ]^(1/3)
h(t) = [ (75t)/(2pi) ]^(1/3)

Answer:
h(t) = [ (75t)/(2pi) ]^(1/3)

============================================================

Part C

Your answer is correct.
Below is an alternative way to find the same answer

--------------------------------------

Plug in the given height; solve for t
h(t) = [ (75t)/(2pi) ]^(1/3)
8 = [ (75t)/(2pi) ]^(1/3)
8^3 = (75t)/(2pi)
512 = (75t)/(2pi)
(75t)/(2pi) = 512
75t = 512*2pi
75t = 1024pi
t = 1024pi/75
At this time value, the height of the water is 8 feet

Set up the radius r(t) function
r = 2*h
r = 2*h(t)
r = 2*[ (75t)/(2pi) ]^(1/3) .... using the answer from part B

Differentiate that r(t) function with respect to t
r = 2*[ (75t)/(2pi) ]^(1/3)
dr/dt = 2*(1/3)*[ (75t)/(2pi) ]^(1/3-1)*d/dt[(75t)/(2pi)]
dr/dt = (2/3)*[ (75t)/(2pi) ]^(-2/3)*(75/(2pi))
dr/dt = (2/3)*(75/(2pi))*[ (75t)/(2pi) ]^(-2/3)
dr/dt = (25/pi)*[ (75t)/(2pi) ]^(-2/3)

Plug in t = 1024pi/75 found earlier above
dr/dt = (25/pi)*[ (75t)/(2pi) ]^(-2/3)
dr/dt = (25/pi)*[ (75(1024pi/75))/(2pi) ]^(-2/3)
dr/dt = (25/pi)*[ (1024pi)/(2pi) ]^(-2/3)
dr/dt = (25/pi)*(1/64)
dr/dt = 25/(64pi)
getting the same answer as before

----------------------------

Thinking back as I finish up, your method is definitely shorter and more efficient. So I prefer your method, which is effectively this:
r = 2h, dr/dh = 2
dh/dt = (25)/(2pi*h^2) ... from part A
dr/dt = dr/dh*dh/dt ... chain rule
dr/dt = 2*((25)/(2pi*h^2))
dr/dt = ((25)/(pi*h^2))
dr/dt = ((25)/(pi*8^2)) ... plugging in h = 8
dr/dt = (25)/(64pi)
which is what you stated in your screenshot (though I added on the line dr/dt = dr/dh*dh/dt to show the chain rule in action)

8 0

3 years ago

Is 2 a solution of 4x +12=4?

mojhsa [17]

Answer:

no

Step-by-step explanation:

4x +12 = 4

4(2) +12 =/= 4

8 +12 =/= 4

8 +12 = 20

(sorry if it doesn't make sense,I tried)

5 0

3 years ago

Read 2 more answers

Explain how you decided on the number of zeros in the product from a b and c

nataly862011 [7]

I think it is b that is the answer

3 0

3 years ago

Lee and Lyn both invested their birthday money. Lee put his money in a savings account that earned 8% simple interest annually.

tatyana61 [14]

Lyn made a better investment.

Her money will grow quicker than Lee because the money grows by 8% annually, and then the next year 8% off of the new balance.

Lee's money will only grow by 8% from the original price.

3 0

3 years ago