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3 years ago

Which of the following is the surface area of the right cylinder below radius 7 height 2

Mathematics

2 answers:

Dimas [21]3 years ago

5 0

7^2 times 2 which is 49.2 and it is 98

juin [17]3 years ago

3 0

$\bf \textit{surface area of a cylinder}\\\\ SA=2\pi r(h+r)~~ \begin{cases} r=radius\\ h=height\\ -----\\ r=7\\ h=2 \end{cases}\implies SA=2\pi (7)(2+7) \\\\\\ SA=14\pi (9)\implies SA=126\pi$

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The size of the largest angle in a triangle is 3 times the size of the smallest angle.

tamaranim1 [39]

The sizes of the angles are 34° , 44° , 102°

Step-by-step explanation:

The given is:

The size of the largest angle in a triangle is 3 times the size of the smallest angle
The third angle is 10° more than the smallest angle
The size of the third angle is x

We need to find the size of each angle in the triangle

∵ The size of the smallest angle = x°

∵ The size of the largest angle is 3 times the size of the smallest angle

∴ The size of the largest angle = x × 3 = (3x)°

∵ The third angle is 10° more than the smallest angle

∴ The size of the third angle = (x + 10)°

Add the size of the three angles and equate the sum by 180°

∵ The sum of the sizes of the interior angles of a Δ is 180°

∴ x + (3x) + (x + 10) = 180

∴ x + 3x + x + 10 = 180

- Add like terms

∴ 5x + 10 = 180

- Subtract 10 from both sides

∴ 5x = 170

- Divide both sides by 5

∴ x = 34

∵ x is the size of the smallest angle

∴ The size of the smallest angle is 34°

∵ 3x is the size of the largest angle

∴ The size of the largest angle = 3(34) = 102°

∵ x + 10 is the size of the third angle

∴ The size of the third angle = 34 + 10 = 44°

The sizes of the angles are 34° , 44° , 102°

Learn more:

You can learn more about the triangles in brainly.com/question/1479138

#LearnwithBrainly

6 0

3 years ago

Mary got a piggy bank as a gift with X cents in it. If she saves Y cents each month for a year, how much money will she have in

-BARSIC- [3]

Answer:

The total money she saved in a year = X + 12Y.

Step-by-step explanation:

Mary got a piggy bank as a gift.

Sum of money in the piggy bank while she got it as a gift = X cents

Sum of money she saved = Y cents per month

1 year = 12 months

So, sum of money she saved in 1 year = Y × 12

= 12Y

Hence, the total money she saved in a year = X + 12Y.

3 0

3 years ago

Find expressions for the partial derivatives of the following functions:

nlexa [21]

Answer:

Step-by-step explanation: partial derivative is the differentiation of one variable e.g. X while leaving the values of the other variable e.g. Y

These four questions A, B, C and D have different functions separated by commas. I will not assume the commas to be something else like a plus sign.

A. f(x) = g'(x).k(y) , g'(x) + h(y)

f(y) = k'(y).g(x) , g(x) + h'(y)

B. f(x) = g'x (x+y)

f(y) = g'y (x+y) , h'y (y+z)

f(z) = h'z (y+z)

C. f(x) = f'x (xy) , f'x (zx)

f(y) = f'y (xy) , f'y (yz)

f(z) = f'z (yz) , f'z (zx)

D. f(x) = f'x (x) , g'(x) , h'x (x,y)

f(y) = h'x (x,y)

These are the partial derivative expressions for each variable in each function. You will need to pay a lot of attention to understand:

* while differentiating X alone, functions in Y which are separated by commas from the functions in X, are ignored totally because they are different questions

* In functions where X added to Y is in a bracket e.g. (x+y), to find the derivative of X, Y isn't thrown away because they are joined (by a plus sign) the derivative of X alone in this case would be f'x (x+y)

* f(x), just like g(x), simply means/represents a function in X hence f'(x) means the differentiation of all X-terms in that function

6 0

3 years ago

Find the slope of the line that passes through (9, 8) and (4, 6).

andreev551 [17]

Answer:

Step-by-step explanation:

7 0

3 years ago

Read 2 more answers

The perimeter of a rectangle is 36m. If its length is increased by 1m and the width is increased by 2m, its area will increase b

maw [93]

Answer:

80 m^2

Step-by-step explanation:

The given information lets you write two equations involving length (x) and width (y).

2(x +y) = 36 . . . . the perimeter is 36 m
(x+1)(y+2) -xy = 30 . . . . increasing the length and width increases area

The second of these equations simplifies to another linear equation, giving a system of linear equations easily solved.

xy +y +2x + 2 -xy = 30

2x +y = 28 . . . . . . . subtract 2

Dividing the first equation by 2 gives

x +y = 18

and subtracting this from the above equation gives ...

(2x +y) -(x +y) = 28 -18

x = 10

Then

y = 18 -10 = 8

The area of the original rectangle is xy = 10·8 = 80 m^2.

4 0

3 years ago