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3 years ago

Please help !!! 3x+8y x = 7 y = -2

Mathematics

1 answer:

Vinil7 [7]3 years ago

4 0

Answer: 5

Step-by-step explanation:

you do each variable individually first, 3(7)=21, 8(-2) is -16, then you add them, 21-16=5 so that is your answer

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The weights of steers in a herd are distributed normally. The standard deviation is 200lbs and the mean steer weight is 900lbs.

katen-ka-za [31]

Answer:

0.0369

Step-by-step explanation:

normalcdf (1220,1320,900,200) is 0.0369

3 0

2 years ago

Find, correct to four decimal places, the length of the curve of intersection of the cylinder 4x2 1 y2 − 4 and the plane x 1 y 1

charle [14.2K]

<u>Answer-</u> Length of the curve of intersection is 13.5191 sq.units

<u>Solution-</u>

As the equation of the cylinder is in rectangular for, so we have to convert it into parametric form with

x = cos t, y = 2 sin t (∵ 4x² + y² = 4 ⇒ 4cos²t + 4sin²t = 4, then it will satisfy the equation)

Then, substituting these values in the plane equation to get the z parameter,

cos t + 2sin t + z = 2

⇒ z = 2 - cos t - 2sin t

∴ $\frac{dx}{dt} = -\sin t$

$\frac{dy}{dt} = 2 \cos t$

$\frac{dz}{dt} = \sin t-2cos t$

As it is a full revolution around the original cylinder is from 0 to 2π, so we have to integrate from 0 to 2π

∴ Arc length

$= \int_{0}^{2\pi}\sqrt{(\frac{dx}{dt})^{2}+(\frac{dy}{dt})^{2}+(\frac{dz}{dt})^{2}$

$=\int_{0}^{2\pi}\sqrt{(-\sin t)^{2}+(2\cos t)^{2}+(\sin t-2\cos t)^{2}$

$=\int_{0}^{2\pi}\sqrt{(2\sin t)^{2}+(8\cos t)^{2}-(4\sin t\cos t)$

Now evaluating the integral using calculator,

$=\int_{0}^{2\pi}\sqrt{(2\sin t)^{2}+(8\cos t)^{2}-(4\sin t\cos t)$ $= 13.5191$

8 0

3 years ago

Help me, please I need this

Alex17521 [72]

Answer:

B) y = -3x - 5

Hope this helps!

Please be kind to mark Brainliest.☺

7 0

4 years ago

X + 2 + x = 22 I need to show my work. Please help. No false answers please.

Minchanka [31]

2x + 2 = 22
2x = 20
X = 10

3 0

3 years ago

Read 2 more answers

The first term of an arithmetic sequence is -5, and the tenth term is 13. Find the common difference.

dlinn [17]

$\bf n^{th}\textit{ term of an arithmetic sequence} \\\\ a_n=a_1+(n-1)d\qquad \begin{cases} n=n^{th}\ term\\ a_1=\textit{first term's value}\\ d=\textit{common difference}\\[-0.5em] \hrulefill\\ a_1=-5\\ n=10\\ a_{10}=13 \end{cases} \\\\\\ a_{10}=a_1+(10-1)d\implies 13=-5+(10-1)d \\\\\\ 13=-5+9d\implies 18=9d\implies \cfrac{18}{9}=d\implies \boxed{2=d}$

7 0

3 years ago