A race car travels 1,212 kilometers in 4 hours. What is the car's rate of speed.

Please answer ASAP will give you five stars

Anastasy [175]

Answer:

628

Step-by-step explanation:

using formula 1/3 x pi x r x r x h

1/3 x 3.14 x 10 x 10 x 6 = 628

4 0

3 years ago

Read 2 more answers

How is using partial products to find the product of two 2-digit factors different and similar

Ierofanga [76]

It is different because you are doing a different method to complete the problem. It is the same because it ends up with the same answer, provided you complete the process correctly.

3 0

3 years ago

The value of a and b

Jlenok [28]

Answer:

Both a and b would both equal 45 degrees

Step-by-step explanation:

To find this, we need to note that a and 135 create a straight line. Since a straight line has 180 degrees, we can create an equation to solve for a.

135 + a = 180

a = 45

Now that we know a is equal to 45, we can tell that b is also equal to that amount. This is because two parallel lines cut by a transversal creates the same angle.

3 0

3 years ago

Consider the equality xy k. Write the following inverse proportion: y is inversely proportional to x. When y = 12, x=5.

skelet666 [1.2K]

Answer:

$y=\dfrac {60} {x}$ or $xy=60$ (depending on your teacher's format preference)

Step-by-step explanation:

<h3><u>Proportionality background</u></h3>

Proportionality is sometimes called "variation". (ex. " 'y' varies inversely as 'x' ")

There are two main types of proportionality/variation:

Direct
Inverse.

Every proportionality, regardless of whether it is direct or inverse, will have a constant of proportionality (I'm going to call it "k").

Below are several different examples of both types of proportionality, and how they might be stated in words:

$y=kx$ y is directly proportional to x
$y=kx^2$ y is directly proportional to x squared
$y=kx^3$ y is directly proportional to x cubed
$y=k\sqrt{x}}$ y is directly proportional to the square root of x
$y=\dfrac {k} {x}$ y is inversely proportional to x
$y=\dfrac {k} {x^2}$ y is inversely proportional to x squared

From these examples, we see that two things:

things that are <u>directly proportional</u> -- the thing is <u>multipli</u>ed to the constant of proportionality "k"
things that are <u>inversely proportional</u> -- the thing is <u>divide</u>d from the constant of proportionality "k".

<h3><u>Looking at our question</u></h3>

In our question, y is inversely proportional to x, so the equation we're looking at is the following $y=\dfrac {k} {x}$ .

It isn't yet clear what the constant of proportionality "k" is for this situation, but we are given enough information to solve for it: "When y=12, x=5."

We can substitute this known relationship pair, and find the "k" that relates this pair of numbers:

<h3><u>Solving for k, and finding the general equation</u></h3>

General Inverse variation equation...

$y=\dfrac {k} {x}$

Substituting known values...

$(12)=\dfrac {k} {(5)}$