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2 years ago

9) Drew bought a chemistry book for $30. Later that book was marked down by 37.5%. What is

Mathematics

1 answer:

kenny6666 [7]2 years ago

8 0

Answer:

$11.25 is the discount

Step-by-step explanation:

30*37.5% = 11.25

that is the discount

so 30-11.25=18.75 is new cost

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Solve for x. Show all work. (10 points)<br><br> 4(2x + 1) - 3= -3(x – 4

Ann [662]

Hello there!

4(2x + 1) - 3 = -3(x - 4)

We need to distribute both sides

(4)(2x) + (4)(1) - 3 = (-3)(x) + (-3)(-4)

8x + 4 - 3 = -3x + 12

8x + 1 = -3x + 12

Now subtract 1 from both sides

8x + 1 - 1 = -3x + 12 - 1

8x = -3x + 11

Add 3x to both sides

8x + 3x = -3x + 11 - 3x

11x = 11

x = 11/11

x = 1

I hope this helps~!

Good luck with your career!

6 0

3 years ago

Kaitaia has one more than 5 times the number or wristbands that shelly has. Rea has three more than twice the number that shelly

saul85 [17]

Answer: The required expression is 3x+4.

Step-by-step explanation:

Since we have given that

Let the number of wristbands that Shelly has be 'x'

Let the number of wristbands that Kaitaia has be $5x+1$

Let the number of wristbands that Rea has be three more than twice the number that shelly has be

$'2x+3'$

According to question, the expression that shows the number of wristbands more Katia has than Rea is given by

$5x+1-(2x-3)\\\\=5x+1-2x+3\\\\=3x+4$

Hence, the required expression is 3x+4.

3 0

3 years ago

Read 2 more answers

#7: Cole plans to purchase a car that depreciates at a rate of 9.2% per

Oliga [24]

Answer:

I'm not really sure but I think the answer is 21,331.20 for 3 year the interst will be 331.20

6 0

2 years ago

If x varies inversely as y, which statement is true?

grin007 [14]

Answer: The Inverse variation

Step-by-step explanation:

The phrase “ y varies inversely as x” or “ y is inversely proportional to x” means that as x gets bigger, y gets smaller, or vice versa. This concept is translated in two ways. yx = k for some constant k, called the constant of proportionality.

3 0

2 years ago

Set up the integral that represents the arc length of the curve f(x) = ln(x) + 5 on [1, 3], and then use Simpson's Rule with n =

marta [7]

Answer:

The integral for the arc of length is:

$\displaystyle\int_1^3\sqrt{1+\frac{1}{x^2}}dx$

By using Simpon’s rule we get: 1.5355453

And using technology we get: 2.3020

The approximation is about 33% smaller than the exact result.

Explanation:

The formula for the length of arc of the function f(x) in the interval [a,b] is:

$\displaystyle\int_a^b \sqrt{1+[f'(x)]^2}dx$

We need the derivative of the function:

$f'(x)=\frac{1}{x}$

And we need it squared:

$[f'(x)]^2=\frac{1}{x^2}$

Then the integral is:

$\displaystyle\int_1^3\sqrt{1+\frac{1}{x^2}}dx$

Now, the Simposn’s rule with n=4 is:

$\displaystyle\int_a^b g(x)}dx\approx\frac{\Delta x}{3}\left( g(a)+4g(a+\Delta x)+2g(a+2\Delta x) +4g(a+3\Delta x)+g(b) \right)$

In this problem:

$a=1,b=3,n=4, \displaystyle\Delta x=\frac{b-a}{n}=\frac{2}{4}=\frac{1}{2},g(x)= \sqrt{1+\frac{1}{x^2}}$

So, the Simposn’s rule formula becomes:

$\displaystyle\int_1^3\sqrt{1+\frac{1}{x^2}}dx\\\approx \frac{\frac{1}{3}}{3}\left( \sqrt{1+\frac{1}{1^2}} +4\sqrt{1+\frac{1}{\left(1+\frac{1}{2}\right)^2}} +2\sqrt{1+\frac{1}{\left(1+\frac{2}{2}\right)^2}} +4\sqrt{1+\frac{1}{\left(1+\frac{3}{2}\right)^2}} +\sqrt{1+\frac{1}{3^2}} \right)$

Then simplifying a bit:

$\displaystyle\int_1^3\sqrt{1+\frac{1}{x^2}}dx \approx \frac{1}{9}\left( \sqrt{1+\frac{1}{1^2}} +4\sqrt{1+\frac{1}{\left(\frac{3}{2}\right)^2}} +2\sqrt{1+\frac{1}{\left(2\right)^2}} +4\sqrt{1+\frac{1}{\left(\frac{5}{2}\right)^2}} +\sqrt{1+\frac{1}{3^2}} \right)$

Then we just do those computations and we finally get the approximation via Simposn's rule:

$\displaystyle\int_1^3\sqrt{1+\frac{1}{x^2}}dx\approx 1.5355453$

While when we do the integral by using technology we get: 2.3020.

The approximation with Simpon’s rule is close but about 33% smaller:

$\displaystyle\frac{2.3020-1.5355453}{2.3020}\cdot100\%\approx 33\%$

8 0

3 years ago