1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
atroni [7]
2 years ago
10

The area of South America is approximately 1.78 × 107 square kilometers. Its population is approximately 3.50 × 108 people. What

is the approximate population density (people per square kilometer) of South America? Write your answer in standard form. If necessary, round your answer to the nearest hundredth.
A: 19.66 people/km^2

B: 1.97 × 10^15 people/km2

C: 5.09 people/km^2

D: 1.97 × 10^1 people/km^2
Mathematics
1 answer:
stepladder [879]2 years ago
6 0

Answer:

<u>A) 19.66 people/km²</u>

Step-by-step explanation:

<u>Given</u>

  • Area of the continent = 1.78 x 10⁷ km²
  • Population = 3.5 x 10⁸ people

<u>To Find</u>

  • Population Density

<u>Solving</u>

  • population density is the number of people per unit area
  • pd = people / area
  • pd = 3.5 x 10⁸ / 1.78 x 10⁷
  • pd = 1.966 x 10
  • pd = <u>19.66 people/km²</u>
You might be interested in
If 24 women can dig a field in 14 days, how long will 16 women take to dig the same field?​
myrzilka [38]
27-28 days, the actual answer is 27.4285714 days, but it depends on how you’re instructed to round your answer
6 0
2 years ago
Simplify the expression -4^2(3x - 7)
maxonik [38]

Answer:

−48x+112

Step-by-step explanation:

evatulate: −16  (3−7)

                -48+112

3 0
3 years ago
Find the slope of the line that contains the points:
Semenov [28]

Answer:

slope is 1

Step-by-step explanation:

5-3/-4--6 = 2/2 = 1

5 0
3 years ago
Read 2 more answers
I PROMISE BRANLIEST TO THE FIRST ANSWER SUBMITTED!
Vedmedyk [2.9K]

Answer:

36

Step-by-step explanation:

because square of term on LHS = square of term on RHS

if 5 - 3y = 6

then (5 - 3y)² = 36

8 0
3 years ago
How do you solve System of Equations?
Katarina [22]

The addition method of solving systems of equations is also called the method of elimination. This method is similar to the method you probably learned for solving simple equations.

If you had the equation "<span>x + 6 = 11</span>", you would write "–6" under either side of the equation, and then you'd "add down" to get "<span>x = 5</span>" as the solution.

<span>x + 6 = 11
    –6    –6
x       =   5</span>

You'll do something similar with the addition method.

<span>Solve the following system using addition.<span>2x + y<span> = 9
3</span>x – y = 16</span>Note that, if I add down, the y's will cancel out. So I'll draw an "equals" bar under the system, and add down:2<span>x + y = 9
3x – y<span> = 16
</span>5x      = 25</span>Now I can divide through to solve for <span>x = 5</span>, and then back-solve, using either of the original equations, to find the value of y. The first equation has smaller numbers, so I'll back-solve in that one:<span><span>2(5) + y = 9
  10 + y = 9
          y = –1</span>Then the solution is <span>(x, y) = (5, –1)</span>.</span></span>

It doesn't matter which equation you use for the backsolving; you'll get the same answer either way. If I'd used the second equation, I'd have gotten:

<span>3(5) – y = 16
  15 – y = 16
        –y = 1
          y = –1</span>

...which is the same result as before.

<span>Solve the following system using addition.<span>x – 2y<span> = –9
</span>x + 3y = 16</span>Note that the x-terms would cancel out if only they'd had opposite signs. I can create this cancellation by multiplying either one of the equations by –1, and then adding down as usual. It doesn't matter which equation I choose, as long as I am careful to multiply the –1<span> through the entire equation. (That means both sides of the "equals" sign!)</span>I'll multiply the second equation.The "–1<span>R2</span>" notation over the arrow indicates that I multiplied row 2 by –1. Now I can solve the equation "<span>–5y = –25</span>" to get <span>y = 5</span>. Back-solving in the first equation, I get:<span><span>x – 2(5) = –9
x – 10 = –9
x = 1</span>Then the solution is <span>(x, y) = (1, 5)</span>.</span></span>

A very common temptation is to write the solution in the form "(first number I found, second number I found)". Sometimes, though, as in this case, you find the y-value first and then the x-value second, and of course in points the x-value comes first. So just be careful to write the coordinates for your solutions correctly. Copyright © Elizabeth Stapel 2003-2011 All Rights Reserved

<span>Solve the following system using addition.<span>2x –   y<span> =     9
3</span>x + 4y = –14</span>Nothing cancels here, but I can multiply to create a cancellation. I can multiply the first equation by 4, and this will set up the y-terms to cancel.Solving this, I get that <span>x = 2</span>. I'll use the first equation for backsolving, because the coefficients are smaller.<span><span>2(2) – y = 9
4 – y = 9
–y = 5
y = –5</span>The solution is <span>(x, y) = (2, –5)</span>.</span></span> <span>Solve the following system using addition. <span> <span><span>  <span><span><span><span /></span></span></span>
<span><span><span /></span></span> </span> <span> <span /></span></span></span></span><span><span>4x – 3y<span> = 25
–3</span>x + 8y = 10</span>Hmm... nothing cancels. But I can multiply to create a cancellation. In this case, neither variable is the obvious choice for cancellation. I can multiply to convert the x-terms to <span>12x</span>'s or the y-terms to <span>24y</span>'s. Since I'm lazy and 12 is smaller than 24, I'll multiply to cancel the x-terms. (I would get the same answer in the end if I set up the y-terms to cancel. It's not that how I'm doing it is "the right way"; it was just my choice. You could make a different choice, and that would be just as correct.)I will multiply the first row by 3 and the second row by 4; then I'll add down and solve.
Solving, I get that <span>y = 5</span>. Neither equation looks particularly better than the other for back-solving, so I'll flip a coin and use the first equation.<span>4x – 3(5) = 25
4x – 15 = 25
4x = 40
x = 10</span>Remembering to put the x-coordinate first in the solution, I get:<span>(x, y) = (10, 5)</span></span>

Usually when you are solving "by addition", you will need to create the cancellation. Warning: The most common mistake is to forget to multiply all the way through the equation, multiplying on both sides of the "equals" sign. Be careful of this.

<span>Solve the following using addition.<span>12x –  13y<span> =   2
–6</span>x + 6.5y = –2</span>I think I'll multiply the second equation by 2; this will at least get rid of the decimal place.Oops! This result isn't true! So this is an inconsistent system (two parallel lines) with no solution (with no intersection point).no solution</span> <span>Solve the following using addition.<span>12x – 3y<span> = 6
  4</span>x –   y = 2</span>I think it'll be simplest to cancel off the y-terms, so I'll multiply the second row by –3.Well, yes, but...? I already knew that zero equals zero. So this is a dependent system, and, solving for "<span>y =</span>", the solution is:<span>y = 4x – 2</span></span>

(Your text may format the answer as "<span>(s, 4s – 2)</span><span>", or something like that.)</span>


6 0
3 years ago
Read 2 more answers
Other questions:
  • glynis drove a golf ball from a point 126 yd north of the ninth hole to a point 53 yd south of the hole. How far did the ball tr
    7·1 answer
  • Evaluate the following expression using the values given:
    9·2 answers
  • James is setting up a fish tank. He is buying a breed of goldfish that typically grows to be 12 inches long . It's recommended t
    7·1 answer
  • Find the measure of an angle whose measure is 50° more than the measure of its complement.
    12·2 answers
  • You earn $1 million per month. What is your annual salary
    14·2 answers
  • Two exponential functions, fand g, are shown in the figure below, where g is a transformation of f.
    8·1 answer
  • Look at the image and thank you
    9·1 answer
  • Find the value of x. <br> (6x+8) <br> (7x-7)
    12·1 answer
  • ( There are two similar triangles on the graph below. Use the graph to answer the questions. You must answer each question AND e
    11·2 answers
  • I am on my trigonometry unit in math and don’t know what to do for this. I also really need work shown!
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!