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3 years ago

Find the area and the circumference of a circle with diameter 6 km

Mathematics

1 answer:

mash [69]3 years ago

4 0

Answer:

$C= 18.84 \ km$

$A = 28.26 \ km$

Step-by-step explanation:

Circumference can be calculated using following formula

$C=2\pi r$ ------------(1)

and area of circle can be calculated using following formula

$A= \pi r^{2}$ ------------(2)

Here diameter d=6 km

Radius (r) is half of diameter

$r= \frac{d}{2} = \frac{6}{2} = 3 \ km$

Now calculate Circumference and diameter using equations (1) and (2) respectively

$C= 2\pi r = 2 (3.14) (3)\\C= 18.84 \ km$

$A= 3.14 (3)^2\\A= 28.26 \ km$

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Solve for equation √-5p=√24-p

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Answer:

Step-by-step explanation:

25,219,829 solved | 850 online

p2-5p-24=0

Two solutions were found :

p = 8

p = -3

Reformatting the input :

Changes made to your input should not affect the solution:

(1): "p2" was replaced by "p^2".

Step by step solution :

Step 1 :

Trying to factor by splitting the middle term

1.1 Factoring p2-5p-24

The first term is, p2 its coefficient is 1 .

The middle term is, -5p its coefficient is -5 .

The last term, "the constant", is -24

Step-1 : Multiply the coefficient of the first term by the constant 1 • -24 = -24

Step-2 : Find two factors of -24 whose sum equals the coefficient of the middle term, which is -5 .

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Step-3 : Rewrite the polynomial splitting the middle term using the two factors found in step 2 above, -8 and 3

p2 - 8p + 3p - 24

Step-4 : Add up the first 2 terms, pulling out like factors :

p • (p-8)

Add up the last 2 terms, pulling out common factors :

3 • (p-8)

Step-5 : Add up the four terms of step 4 :

(p+3) • (p-8)

Which is the desired factorization

Equation at the end of step 1 :

(p + 3) • (p - 8) = 0

Step 2 :

Theory - Roots of a product :

2.1 A product of several terms equals zero.

When a product of two or more terms equals zero, then at least one of the terms must be zero.

We shall now solve each term = 0 separately

In other words, we are going to solve as many equations as there are terms in the product

Any solution of term = 0 solves product = 0 as well.

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2.2 Solve : p+3 = 0

Subtract 3 from both sides of the equation :

p = -3

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2.3 Solve : p-8 = 0

Add 8 to both sides of the equation :

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3 years ago

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morpeh [17]

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Step-by-step explanation:

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3 years ago

On Friday, a fruit stand sold a total of 92 apples and oranges. On Saturday, the fruit stand sold four times the number of apple

andreev551 [17]

Option A : a+o = 92 , 4a+2o = 284 is the right answer

Step-by-step explanation:

Let o be the number of oranges sold on Friday and

a be the number of apples sold on Friday

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A total of 92 was sold on Friday will yield the equation

$a+o = 92$

On Saturday,

4 times the number of apples = 4a

2 times the number of oranges = 2o

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$4a+2o = 284$

Hence,

The system of equations is:

$a+o = 92\\4a+2o = 284$

Option A : a+o = 92 , 4a+2o = 284 is the right answer

Keywords: Linear equations, variables

Learn more about linear equations at:

#LearnwithBrainly

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