The most efficient first step in the process to factor the trinomial 4x^3-20x^2+24x

Work out the surface area of a cylinder when the height = 18cm and the volume = 1715cm cubed

lara [203]

Answer:

813.4 cm² (nearest tenth)

Step-by-step explanation:

Volume of a cylinder

$\sf V=\pi r^2 h \quad\textsf{(where r is the radius and h is the height)}$

Given:

h = 18cm
V = 1715 cm³

Use the Volume of a Cylinder formula and the given values to find the radius of the cylinder:

$\implies \sf 1715=\pi r^2 (18)$

$\implies \sf r^2=\dfrac{1715}{18 \pi}$

$\implies \sf r=\sqrt{\dfrac{1715}{18 \pi}$

Surface Area of a Cylinder

$\sf SA=2 \pi r^2 + 2 \pi r h \quad\textsf{(where r is the radius and h is the height)}$

Substitute the given value of h and the found value of r into the formula and solve for SA:

$\implies \sf SA=2 \pi \left(\sqrt{\dfrac{1715}{18 \pi}\right)^2 + 2 \pi \left(\sqrt{\dfrac{1715}{18 \pi}\right)(18)$

$\implies \sf SA=2 \pi \left(\dfrac{1715}{18 \pi} \right) + 36 \pi \left(\sqrt{\dfrac{1715}{18 \pi}\right)$

$\implies \sf SA=\dfrac{1715}{9} + 36 \pi \left(\sqrt{\dfrac{1715}{18 \pi}\right)$

$\implies \sf SA=813.3908956...$

Therefore, the surface area of the cylinder is 813.4 cm² (nearest tenth)

8 0

2 years ago

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If f(x) = x + 15, find f(3)

gavmur [86]

Answer:

I think its 18

Step-by-step explanation:

3 0

2 years ago

Pls help me with this

yKpoI14uk [10]

Answer:

c. 2144

Step-by-step explanation:

i searched it up

8 0

3 years ago

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PLEASEEEE ANSWER ASAP!!!!

Reil [10]

Refer to the attached image.

Let the width of the border be 'x' inch.

Area of border = Area of rectangle ABCD - Area of rectangle PQRS

Area of rectangle ABCD = $length \times width$

= $AB \times BC$

= $(13+2x) \times (9+2x)$ square units.

Area of rectangle PQRS = $PQ \times RQ$

= $13 \times 9$

= 117 square units.

So, area of border = $(13+2x)(9+2x)-117 = 48$

As it is given that the area of border is 48 square units.

So, $117+26x+18x+4x^2-117 = 48$

$44x + 4x^2-48=0$

$4x^2 + 44x = 48$

So, the complete equation is $4x^2 + 44x = 48$ .

Now, we will find 'x' in the equation $x^2+11x-12=0$ ,

$x^2 + 12x - x -12 =0$

$x(x+12)-1(x+12)=0$

(x-1) (x+12)=0

So, x = 1 or x = -12

Width can'not be negative.

So, x = 1 .

Therefore, the width of the border can'not be 2.5 inch.

Therefore, the width of the border is 1 inch.

5 0

2 years ago

Which number is in the solution set of the inequality x > -4 -2 -6 -8 -10

Alik [6]

Answer:

-2

Step-by-step explanation:

The inequality is x is greater than -4.

-6, -8, and -10 are all less than -4.

-2 is the only one greater than.

6 0

2 years ago

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