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3 years ago

Can anyone explain how to find surface area? BRAINLIEST FOR BEST EXPLAINTION!

1 answer:

6 0

Surface Area of a Cube = 6 a 2

(a is the length of the side of each edge of the cube)

In words, the surface area of a cube is the area of the six squares that cover it. The area of one of them is a*a, or a 2 . Since these are all the same, you can multiply one of them by six, so the surface area of a cube is 6 times one of the sides squared.

Surface Area of a Rectangular Prism = 2ab + 2bc + 2ac
(a, b, and c are the lengths of the 3 sides)

In words, the surface area of a rectangular prism is the area of the six rectangles that cover it. But we don't have to figure out all six because we know that the top and bottom are the same, the front and back are the same, and the left and right sides are the same.

The area of the top and bottom (side lengths a and c) = a*c. Since there are two of them, you get 2ac. The front and back have side lengths of b and c. The area of one of them is b*c, and there are two of them, so the surface area of those two is 2bc. The left and right side have side lengths of a and b, so the surface area of one of them is a*b. Again, there are two of them, so their combined surface area is 2ab.

Surface Area of Any Prism

(b is the shape of the ends)

Surface Area = Lateral area + Area of two ends

(Lateral area) = (perimeter of shape b) * L

Surface Area = (perimeter of shape b) * L+ 2*(Area of shape b)

Surface Area of a Sphere = 4 pi r 2

(r is radius of circle)

Surface Area of a Cylinder = 2 pi r 2 + 2 pi r h

(h is the height of the cylinder, r is the radius of the top)

Surface Area = Areas of top and bottom +Area of the side

Surface Area = 2(Area of top) + (perimeter of top)* height

Surface Area = 2(pi r 2) + (2 pi r)* h

In words, the easiest way is to think of a can. The surface area is the areas of all the parts needed to cover the can. That's the top, the bottom, and the paper label that wraps around the middle.

You can find the area of the top (or the bottom). That's the formula for area of a circle (pi r2). Since there is both a top and a bottom, that gets multiplied by two.

The side is like the label of the can. If you peel it off and lay it flat it will be a rectangle. The area of a rectangle is the product of the two sides. One side is the height of the can, the other side is the perimeter of the circle, since the label wraps once around the can. So the area of the rectangle is (2 pi r)* h.

Add those two parts together and you have the formula for the surface area of a cylinder.

Surface Area = 2(pi r 2) + (2 pi r)* h

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The Mason High Cougars need to win 3 out of the next 12 baseball games to make it to

natta225 [31]

Answer:

The percent for 3 out of 12 is 25%

If the total number of games was 100, the win amount would need to be 25.

Step-by-step explanation:

3 out of 12 is a fraction - 3/12

3/12 = 0.25 which means 25% because 0.25 is 25% of 1.

Using the same percentage for 100 total games, you just multiply 100 by 0.25, the decimal version of the percentage.

3 0

3 years ago

PLZ HELP ME!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!During a 4-month-long drought, the water level in a lake changed

Dafna1 [17]

Answer:

-78

Step-by-step explanation:

4 Months is -312 so dividing by 4 will give the decrease of one month:

-312 ÷ 4 = -78

3 0

3 years ago

Which number is eqyal to 13

Ostrovityanka [42]

Answer:
XIII

Hope this helps

6 0

2 years ago

Use the formula to find the area use 3.14 for pie the circle is 15 cm

alexandr402 [8]

Hey there!

$A= \pi r^2$

By using this formula, we plug it in.

Your correct answer would be . . .

$A$ ≈ $\boxed{\boxed{706.86}}$

Hope this helps.
~Jurgen

5 0

3 years ago

Which values are possible rational roots of 4x3+9x2−x+10=0 according to the rational root theorem? Select each correct answer. ±

navik [9.2K]

ANSWER

The possible rational roots are:

$\pm\frac{1}{2},\pm2,\pm \frac{5}{2}$

EXPLANATION

According to the rational root theorem, the possible rational roots of the polynomial,

$4x^3+9x^2-x+10=0$

are all the possible factors of the constant term divided by all the possible factors of the coefficient of the highest degree of the polynomial.

Therefore we examine the numerator and denominator of the options provided to see if they are factors of 10 and 4 respectively.

For

$\pm\frac{1}{2}$ , we can see that 1 is a factor of 10 and 2 is a factor of 4, hence it is a possible rational root.

The same thing applies to $\pm2,\pm \frac{5}{2}$ also.

As for

$\pm \frac{2}{5}$ , 2 is a factor of 10 but 5 is not a factor of 2, hence it is not a possible rational root.

5 0

3 years ago