A. for the circumference it is C=pi(d)=pi(2r)=pi(10)= 31.4 ft
b. for the area it is A=pi(r)^2=pi(5)^2=pi(25)= 78.5 ft squared
c. since the are is 78.5 ft squared multiply by $4.50= $353.25 to floor the circle.

6 0

3 years ago

Given points A(-1, -2) and B(2, 4) where AP: BP=1:2, find the locus of point P.

koban [17]

Answer:

$x^2 + 4x + y^2 +8y = 0$

Step-by-step explanation:

Given

$A = (-1,-2)$

$B = (2,4)$

$AP:BP = 1 : 2$

Required

The locus of P

$AP:BP = 1 : 2$

Express as fraction

$\frac{AP}{BP} = \frac{1}{2}$

Cross multiply

$2AP = BP$

Calculate AP and BP using the following distance formula:

$d = \sqrt{(x - x_1)^2 + (y - y_1)^2}$

So, we have:

$2 * \sqrt{(x - -1)^2 + (y - -2)^2} = \sqrt{(x - 2)^2 + (y - 4)^2}$

$2 * \sqrt{(x +1)^2 + (y +2)^2} = \sqrt{(x - 2)^2 + (y - 4)^2}$

Take square of both sides

$4 * [(x +1)^2 + (y +2)^2] = (x - 2)^2 + (y - 4)^2$

Evaluate all squares

$4 * [x^2 + 2x + 1 + y^2 +4y + 4] = x^2 - 4x + 4 + y^2 - 8y + 16$

Collect and evaluate like terms

$4 * [x^2 + 2x + y^2 +4y + 5] = x^2 - 4x + y^2 - 8y + 20$

Open brackets

$4x^2 + 8x + 4y^2 +16y + 20 = x^2 - 4x + y^2 - 8y + 20$

Collect like terms

$4x^2 - x^2 + 8x + 4x + 4y^2 -y^2 +16y + 8y + 20 - 20 = 0$

$3x^2 + 12x + 3y^2 +24y = 0$

Divide through by 3

$x^2 + 4x + y^2 +8y = 0$

3 0

3 years ago

In the video, the water level was 15 milliliters before adding the chain, and 20 milliliters after adding the chain. When I weig

mr_godi [17]

Answer:

39.7%

Explanation:

1. First find the density of your chain

Density = mass / volume

Volume = displaced water volume

= Volume of Final level of water - initial level of water

= 20 ml - 15 ml = 5 ml

Mass = 66.7 g

Density = 66.7g / 5 ml = 13.34 g/ml

2. Second, write the denisty of the chain as the weighted average of the densities of the other metals:

Mass of gold × density of gold + mass of other metals × density of other metals, all divided by the mass of the chain.

Calling x the amount of gold, then the amount of other metals is 66.7 - x:

$\dfrac{19.3\cdot x+9.7\cdot (66.7-x)}{66.7}=13.34$

$19.3x+635.66-9.7x=889.778$

$9.6x=254.118\\\\x=26.47$

Then, there are 26.47 grams of gold in 66.7 grams of chain, which yields a percentage of:

(26.47 / 66.7) × 100 = 39.7%

7 0

3 years ago

Simplify fully e x e x e x f/ e x e x f x f

mel-nik [20]

Given:

The given expression is

$\dfrac{e\times e\times e\times f}{e\times e\times f\times f}$

To find:

The simplified form of given expression.

Solution:

We have,

$\dfrac{e\times e\times e\times f}{e\times e\times f\times f}$

The common factors in numerator and denominator are e, e, f.

Cancel out the common factors.

$=\dfrac{e}{f}$

Therefore, the required expression is $\dfrac{e}{f}$ .

6 0

3 years ago