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2 years ago

Solve for y in the equation: y over 5 = -15

Mathematics

2 answers:

nikdorinn [45]2 years ago

8 0

Answer:

y = -75

Step-by-step explanation:

Simplify both sides of equation

1/5y = -15

multiply both side by 5

1/5y * 5 = -15 * 5

y = -75

Iteru [2.4K]2 years ago

7 0

Answer:

y=-75

Step-by-step explanation:

y/5=-15

y=-15*5

y=-75

You might be interested in

Newton's law of cooling is:

Mnenie [13.5K]

Answer:

$t = \frac{ln(\frac{21}{59})}{-0.15}=6.887 hr$

So it would takes approximately 6.9 hours to reach 32 F.

Step-by-step explanation:

For this case we have the following differential equationÑ

$\frac{du}{dt}= -k (u-T)$

We can reorder the expression like this:

$\frac{du}{u-T} = -k dt$

We can use the substitution $w = u-T$ and $dw =du$ so then we have:

$\frac{dw}{w} =-k dt$

IF we integrate both sides we got:

$ln |w| = -kt +C$

If we apply exponential in both sides we got:

$w = e^{-kt} *e^c$

And if we replace w = u-T we got:

$u(t)= T + C_1 e^{-kt}$

We can also express the solution in the following terms:

$u(t) = (T_i -T_{amb}) e^{kt} +T_{amb}$

For this case we know that $k =-0.15 hr$ since w ehave a cooloing, $T_{i}= 70 F, T_{amb}=11F$ , we have this model:

$u(t) = (70-11) e^{-0.15t} +11$

And if we want that the temperature would be 32F we can solve for t like this:

$32 = 59 e^{-0.15 t} +11$

$21=59 e^{-0.15 t}$

$\frac{21}{59} = e^{-0.15 t}$

If we apply natural logs on both sides we got:

$ln (\frac{21}{59}) =-0.15 t$

$t = \frac{ln(\frac{21}{59})}{-0.15}=6.887 hr$

So it would takes approximately 6.9 hours to reach 32 F.

7 0

3 years ago

The table lists how poverty level income cutoffs (in dollars) for a family of four have changed over time. Use the midpoint for

frez [133]

The poverty level cutoff in 1987 to the nearest dollar was $10787.

<h3>How to find a midpoint?</h3>

The midpoint as the point that divides the line segment exactly in half having two equal segments. Therefore, the midpoint presents the same distance between the endpoints for the line segment. The midpoint formula is: $\mathrm{Midpoint\:of\:}\left(x_1,\:y_1\right),\:\left(x_2,\:y_2\right):\quad \left(\frac{x_2+x_1}{2},\:\:\frac{y_2+y_1}{2}\right)$ .

For solving this exercise, first you need plot the points in a chart. See the image.

Your question asks to approximate the poverty level cutoff in 1987 to the nearest dollar using the midpoint formula. Note that the year 1987 is between 1980 and 1990, thus you should apply the midpoint formula from data for this year (1987).

$\mathrm{Midpoint\:of\:}\left(1980,8429),\:\left(1990,13145):\quad \left(\frac{1990+1980}{2},\:\:\frac{13145+8429}{2}\right)\\\\ \\$

$\mathrm{Midpoint\:of\:}\left(1980,8429)\:=\left(\frac{1990+1987}{2},\:\frac{13145+3843}{2}\right)\\ \\ =\left(\frac{3977}{2},\:\frac{21574}{2}\right)$

$\mathrm{Midpoint\:of\:}\left(1980,8429)\:=\=(\frac{3977}{2},10787)$

The answer for your question will be the value that you calculated for the y-coordinate. Then, the poverty level cutoff in 1987 to the nearest dollar was $10787.

Read more about the midpoint segment here:

brainly.com/question/11408596

7 0

1 year ago

Work out size of angle x

myrzilka [38]

Answer:

Step-by-step explanation:

Comment

You are given values for the adjacent side of <x and the hypotenuse of a right triangle. This defines the Cosine of an angle

Equation

Cos(x) = a/c the way you have labeled it.

Givens

a = 9

c = 18

Solution

Cos(x) = a / c

Cos(x) = 9 / 18

cos(x) = 1/2

x = cos-1(1/2)

x = 60 degrees

Answer

x = 60

7 0

2 years ago

Read 2 more answers

If a paper plane is thrown from the top of a 147-foot cliff into the water below, the height of the plane at any given time can

sasho [114]

Answer:

c. 6.5 seconds.

Step-by-step explanation:

We have been given that a a paper plane is thrown from the top of a 147-foot cliff into the water below, the height of the plane at any given time can be determined by the formula $h = -3t^2+147$ , where h is the height of the plane at t seconds.

To find the time, when plane will be at a height of exactly 20.25 feet, we will substitute $h=20.25$ in our given formula and solve for t as:

$20.25= -3t^2+147$

$-3t^2+147=20.25$

$-3t^2+147-147=20.25-147$

$-3t^2=-126.75$

$\frac{-3t^2}{-3}=\frac{-126.75}{-3}$

$t^2=42.25$

Take square root of both sides:

$t=\pm \sqrt{42.25}$

$t=\pm 6.5$

Since time cannot be negative, therefore, the plane will be at a height of exactly 20.25 feet after 6.5 seconds and option 'c' is the correct choice.

6 0

3 years ago

2(a=4)=2a-8+4a solve for a

Naddik [55]

Answer:

a = 0.

Step-by-step explanation:

2(a - 4) = 2a - 8 + 4a

2a - 8 = 2a - 8 + 4a

2a - 2a - 4a = -8 + 8

-4a = 0

a = 0.

8 0

2 years ago