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2 years ago

15

15 POINTS!

1 answer:

jok3333 [9.3K]2 years ago

8 0

The answer is 7x20 and that equals 140 good luck

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What is the measurement

Blizzard [7]

Answer:

X=135 degrees

Step-by-step explanation:

the total interior angle of a triangle is 180.

To work this out you would first add the interior angles of B which is 69 and the interior angle of C which is 66, which gives you 135.

The next step is to minus 135 from 180, which gives you 45. This is because the total interior angle of a triangle is 180.

Then to work out the angle of x you would minus 45 from `180, which gives you 135. This is because the total angle in a straight line is 180 degrees.

1) Add the angles of 69 and 66.

$69+66=135\\$

2) Minus 135 from 180.

$180-135=45$

3) Minus 180 from 45.

$180-45=135 degrees$

3 0

2 years ago

The radius of a cone is increasing at a constant rate of 7 meters per minute, and the volume is decreasing at a rate of 236 cubi

storchak [24]

Answer:

The rate of change of the height is 0.021 meters per minute

Step-by-step explanation:

From the formula

$V = \frac{1}{3}\pi r^{2}h$

Differentiate the equation with respect to time t, such that

$\frac{d}{dt} (V) = \frac{d}{dt} (\frac{1}{3}\pi r^{2}h)$

$\frac{dV}{dt} = \frac{1}{3}\pi \frac{d}{dt} (r^{2}h)$

To differentiate the product,

Let r² = u, so that

$\frac{dV}{dt} = \frac{1}{3}\pi \frac{d}{dt} (uh)$

Then, using product rule

$\frac{dV}{dt} = \frac{1}{3}\pi [u\frac{dh}{dt} + h\frac{du}{dt}]$

Since $u = r^{2}$

Then, $\frac{du}{dr} = 2r$

Using the Chain's rule

$\frac{du}{dt} = \frac{du}{dr} \times \frac{dr}{dt}$

∴ $\frac{dV}{dt} = \frac{1}{3}\pi [u\frac{dh}{dt} + h(\frac{du}{dr} \times \frac{dr}{dt})]$

Then,

$\frac{dV}{dt} = \frac{1}{3}\pi [r^{2} \frac{dh}{dt} + h(2r) \frac{dr}{dt}]$

Now,

From the question

$\frac{dr}{dt} = 7 m/min$

$\frac{dV}{dt} = 236 m^{3}/min$

At the instant when $r = 99 m$

and $V = 180 m^{3}$

We will determine the value of h, using

$V = \frac{1}{3}\pi r^{2}h$

$180 = \frac{1}{3}\pi (99)^{2}h$

$180 \times 3 = 9801\pi h$

$h =\frac{540}{9801\pi }$

$h =\frac{20}{363\pi }$

Now, Putting the parameters into the equation

$\frac{dV}{dt} = \frac{1}{3}\pi [r^{2} \frac{dh}{dt} + h(2r) \frac{dr}{dt}]$

$236 = \frac{1}{3}\pi [(99)^{2} \frac{dh}{dt} + (\frac{20}{363\pi }) (2(99)) (7)]$

$236 \times 3 = \pi [9801 \frac{dh}{dt} + (\frac{20}{363\pi }) 1386]$

$708 = 9801\pi \frac{dh}{dt} + \frac{27720}{363}$

$708 = 30790.75 \frac{dh}{dt} + 76.36$

$708 - 76.36 = 30790.75\frac{dh}{dt}$

$631.64 = 30790.75\frac{dh}{dt}$

$\frac{dh}{dt}= \frac{631.64}{30790.75}$

$\frac{dh}{dt} = 0.021 m/min$

Hence, the rate of change of the height is 0.021 meters per minute.

3 0

2 years ago

3/5 × -4/7 + 4/35 - 3/10 × 4/7

Annette [7]

Answer:

I think its -2/5 but not sure

Step-by-step explanation:

5 0

2 years ago

Read 2 more answers

____% of 25 is 3 i need help with this paperany help with this papers

ra1l [238]

Answer: 12

Step-by-step explanation:

3 0

2 years ago

the ratio of goats to sheep at a university research farm is 4: 7. The number of sheep at the arm is 28. what is the number of g

GalinKa [24]

4+7=11 i.e. The whole.
7/11=28

1/11=4
Goats are 4/11 therefore
4 x 4= Ans
All the animals add up to 44 and if you check w/ 7/11 it is correct.

4 0

2 years ago