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Serhud [2]
3 years ago
8

If 30% of students failed their last test, and there were 40 students that took the test, how many students failed?

Mathematics
1 answer:
Gnom [1K]3 years ago
8 0

Answer:

12.

Step-by-step explanation:

30% of 40 is 12. To calculate x% of a number y, we use the following rule: x% of y = (x / 100) × y.

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Carlos buys a vintage automobile for $7300. He estimates that the value will increase by 3% every year. Estimate the value of th
lakkis [162]

Answer:

$9810.59

General Formulas and Concepts:

<u>Pre-Algebra</u>

Order of Operations: BPEMDAS

  1. Brackets
  2. Parenthesis
  3. Exponents
  4. Multiplication
  5. Division
  6. Addition
  7. Subtraction
  • Left to Right<u> </u>

<u>Algebra I</u>

Simple Interest Rate Formula: \displaystyle A = P(1 + r)^t

  • <em>P</em> is principle amount
  • <em>r</em> is rate
  • <em>t</em> is time (in years)

Step-by-step explanation:

<u>Step 1: Define</u>

<em>Identify variables</em>

<em>P</em> = 7300

<em>r</em> = 3% = 0.03

<em>t</em> = 10

<u>Step 2: Solve for </u><em><u>A</u></em>

  1. Substitute in variables [Simple Interest Rate Formula]:                                 \displaystyle A = 7300(1 + 0.03)^{10}
  2. (Parenthesis) Add:                                                                                            \displaystyle A = 7300(1.03)^{10}
  3. Evaluate exponents:                                                                                         \displaystyle A = 7300(1.34392)
  4. Multiply:                                                                                                              \displaystyle A = 9810.59
7 0
3 years ago
Distributive property combined like term.... 3(x+2)+14-7x
GaryK [48]
First you would distribute the 3. So it would be (3x+6)+14+7x. Since you can’t do anything inside the parentheses, you drop them. Then you’d combine like terms. 3x+7x is 10x, and 14+6 is 20. That would get you your answer, 10x+20
5 0
3 years ago
Pls help I just need the answer​
inn [45]
That’s mainey me too
8 0
3 years ago
X2 + y2 + 42x + 38y − 47 = 0. The equation of this circle in standard form is
erastova [34]

The Standard form of the equation of circle is (x+21)² + (y+19)² = 849

<h3>What is Standard form of circle?</h3>

To transform general form to a standard form, you can use completing the square method or you can convert this equation

x² + y² + Dx + Ey + F = 0 to x² + y² + (-2h)x + (-2k)y + (h²+k²-r²) = 0

Here, Given: x² + y² + 42x + 38y − 47 = 0

Required: Find the values of h, k, and r using this formula

x² + y² + (-2h)x + (-2k)y + (h²+k²-r²) = 0

On comparing we get,

-2h = 42

  h = 21

-2k = 38

 k = 19

-47 = h² + k² - r²

-47 = 21² + 19² - r²

   r² = 849

  r = √849

Thus, the Standard form of the equation of circle is (x+21)² + (y+19)² = 849

Learn more about Circle from:

brainly.com/question/11833983

#SPJ1

7 0
2 years ago
Use the two point (0,9) and (8,5) to write the equation in slope-intercept form.
Monica [59]

Answer:

y = -1/2x + 9

Step-by-step explanation:

(0, 9) and (8, 5)

First you want to find the slope of the line that passes through these points. To find the slope of the line, we use the slope formula: (y₂ - y₁) / (x₂ - x₁)

Plug in these values:

(5 - 9) / (8 - 0)

Simplify the parentheses.

= (-4) / (8)

Simplify the fraction.

-4/8

= -1/2

This is your slope. Plug this value into the standard slope-intercept equation of y = mx + b.

y = -1/2x + b

To find b, we want to plug in a value that we know is on this line: in this case, I will use the second point (8, 5). Plug in the x and y values into the x and y of the standard equation.

5 = -1/2(8) + b

To find b, multiply the slope and the input of x(8)

5 = -4 + b

Now, add 4 to both sides to isolate b.

9 = b

Plug this into your standard equation.

y = -1/2x + 9

This is your equation.

Check this by plugging in the other point you have not checked yet (0, 9).

y = -1/2x + 9

9 = -1/2(0) + 9

9 = 0 + 9

9 = 9

Your equation is correct.

Hope this helps!

6 0
3 years ago
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