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3 years ago

S = 2πrh + 2πr², for h

Mathematics

1 answer:

diamong [38]3 years ago

6 0

Answer:

Step-by-step explanation:

This is a literal equation, and for some reason, students literally freak out about solving them. We will isolate h the same way we would if we were solving an equation for x. In order to get the term with the h in it all by itself, we have to move everything else away from that term. The 2πr² is added on the left, so we will move it by subtracting it from both sides, giving us

$S-2\pi r^2=2\pi rh$

Then we need to get the h alone. Everything on the right side of the equals sign is multiplied together, so the "undoing" of multiplication is division, so that's what we'll do. Divide everything away from the h:

$\frac{S-2\pi r^2}{2\pi r}=h$

which is choice C.

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3 years ago

A cone-shaped paper drinking cup is to be made to hold 33 cm3 of water. find the height and radius of the cup that will use the

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3 years ago

In a shipment of 56 vials, only 13 do not have hairline cracks. If you randomly select 3 vials from the shipment, in how many wa

Elden [556K]

Answer: 27434

Step-by-step explanation:

Given : Total number of vials = 56

Number of vials that do not have hairline cracks = 13

Then, Number of vials that have hairline cracks =56-13=43

Since , order of selection is not mattering here , so we combinations to find the number of ways.

The number of combinations of m thing r things at a time is given by :-

$^nC_r=\dfrac{n!}{r!(n-r)!}$

Now, the number of ways to select at least one out of 3 vials have a hairline crack will be :-

$^{13}C_2\cdot ^{43}C_{1}+^{13}C_{1}\cdot ^{43}C_{2}+^{13}C_0\cdot ^{43}C_{3}\\\\=\dfrac{13!}{2!(13-2)!}\cdot\dfrac{43!}{1!(42)!}+\dfrac{13!}{1!(12)!}\cdot\dfrac{43!}{2!(41)!}+\dfrac{13!}{0!(13)!}\cdot\dfrac{43!}{3!(40)!}\\\\=\dfrac{13\times12\times11!}{2\times11!}\cdot (43)+(13)\cdot\dfrac{43\times42\times41!}{2\times41!}+(1)\dfrac{43\times42\times41\times40!}{6\times40!}\\\\=3354+11739+12341=27434$

Hence, the required number of ways =27434

5 0

3 years ago

someone please explain to me how to find the area PLEASE! Find the area and perimeter of quadrilateral ABCD below. Explain your

Lunna [17]

Answer:

Part A) The area of the figure is $24\ units^{2}$

Part B) The perimeter of the figure is $20\ units$

Step-by-step explanation:

step 1

Find the area of the figure

we know that

The area of the figure is equal to the area of triangle ABD plus the area of triangle BCD

The area of triangle is equal to

$A=\frac{1}{2}bh$

<u>Area of triangle ABD</u>

Observing the graph

$b=BD=(-2+8)=6\ units$

$h=(9-5)=4\ units$

substitute

$A=\frac{1}{2}(6)(4)=12\ units^{2}$

<u>Area of triangle BCD</u>

Observing the graph

$b=BD=(-2+8)=6\ units$

$h=(5-1)=4\ units$

substitute

$A=\frac{1}{2}(6)(4)=12\ units^{2}$

The area of the figure is

$12\ units^{2}+12\ units^{2}=24\ units^{2}$

step 2

Find the perimeter of the figure

we know that

The perimeter of the figure is equal to

$P=AB+BC+CD+AD$

we have

$A(-5,1),B(-8,5),C(-5,9),D(-2,5)$

the formula to calculate the distance between two points is equal to

$d=\sqrt{(y2-y1)^{2}+(x2-x1)^{2}}$

Find the distance AB

$d=\sqrt{(5-1)^{2}+(-8+5)^{2}}=5\ units$

Find the distance BC

$d=\sqrt{(9-5)^{2}+(-5+8)^{2}}=5\ units$

Find the distance CD

$d=\sqrt{(5-9)^{2}+(-2+5)^{2}}=5\ units$

Find the distance AD

$d=\sqrt{(5-1)^{2}+(-2+5)^{2}}=5\ units$

substitute the values

$P=5+5+5+5=20\ units$

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3 years ago

Hey there guys could anyone help me out here? tutors are unavailable and help would really be appreciated.

Scilla [17]

Answer:

50 degrees

Step-by-step explanation:

because it is a parallelogram, angle B = angle D, and angle C = angle A

that means we have 130(2) = 260 degrees that we know.

the total interior angles of a parallelogram = 360

360 - 260 = 100 degrees left. BUT because those are the total amount of angles left, those are angles A and C combined, so you have to divide 100 in half to get the angle A/ angle DAB

100/2 = 50 degrees. hope this helps! leave a question if you are still confused.

5 0

3 years ago

Read 2 more answers