Frank is on the swim team. each day he swims 850m . how many kilometers does he swim each day?

The distance around the middle of a sphere (the circumference) equals 37.699 in. what is the surface area of the sphere?

podryga [215]

To solve this problem you must apply the proccedure shown below:

1. Clear the radius from the formula for the circumference of a circle and substitute values, as following:

$C=2\pi r\\ r=C/2\pi \\ r=37.699in/2\pi \\ r=5.99in$

2. Substitute the radius calculated into the formula for calculate the surface area of the sphere:

$SA=4\pi r^{2} \\ SA=4\pi(5.99in^{2})\\ SA=450.88in^{2}$

The answer is: $450.88in^{2}$

5 0

3 years ago

The area of a rectangular piece of cardboard is represented by

Liula [17]

This question is solved applying the formula of the area of the rectangle, and finding it's width. To do this, we solve a quadratic equation, and we get that the cardboard has a width of 1.5 feet.

Area of a rectangle:

The area of rectangle of length l and width w is given by:

$A = wl$

w(2w + 3) = 9

From this, we get that:

$l = 2w + 3, A = 9$

Solving a quadratic equation:

Given a second order polynomial expressed by the following equation:

$ax^{2} + bx + c, a\neq0$ .

This polynomial has roots $x_{1}, x_{2}$ such that $ax^{2} + bx + c = a(x - x_{1})*(x - x_{2})$ , given by the following formulas:

$x_{1} = \frac{-b + \sqrt{\Delta}}{2*a}$

$x_{2} = \frac{-b - \sqrt{\Delta}}{2*a}$

$\Delta = b^{2} - 4ac$

In this question:

$w(2w+3) = 9$

$2w^2 + 3w - 9 = 0$

Thus a quadratic equation with $a = 2, b = 3, c = -9$

Then

$\Delta = 3^2 - 4(2)(-9) = 81$

$w_{1} = \frac{-3 + \sqrt{81}}{2*2} = 1.5$

$w_{2} = \frac{-3 - \sqrt{81}}{2*2} = -3$

Width is a positive measure, thus, the width of the cardboard is of 1.5 feet.

Another similar problem can be found at brainly.com/question/16995958

5 0

2 years ago

How do you solve 10.50 X 8.5

emmasim [6.3K]

Answer:

89.25

Step-by-step explanation:

because:

it just is

6 0

2 years ago

9n+21−3n−24 simplify

Thepotemich [5.8K]

Alright First you combine the like terms.
9n - 3n = 6n
21 - 24 = -3

Rewrite the simplified equation
6n - 3 = 0

Solve for n
6n = 3
n = 3/6
n = 1/2

Ask if you need more help! :)

6 0

3 years ago

The graph below shows the time Andrea spent reading one day. Write a few sentences to describe the relationship between the time

Alex777 [14]

Answer:

Step-by-step explanation:

Well, there are several relationships you can describe. As time increases how does number of pages react? Like does it increase or decrease. Is it always increasing or decreasing by the same amount? If it's not all the same how do different parts look different.

There aren't any actual numbers, so you can't say specifically how they relate, like you can't say she read 5 pages a minute or something.

3 0

2 years ago

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