Plz answer this (5x^2-3x+1)-(4x+2x^2-2)

If the length of each side of a cube is doubled, is the surface area doubled? Use an example to support your answer

sashaice [31]

If a = 6l^2 is the total area of the surface of a cube with sides l length and A = 6 (2l)^2 is that area with 2l sides, then we take the ratio A/a = 6 (2l)^2/(6 l^2) = (2l)^2/l^2 = 4l^2/l^2 = 4. So that A = 4a. And that explicitly shows that the area A with 2l for sides is 4 X a, where a is the area when l is the side length.

Using ratios to compare values of the same thing is the smart way to solve this kind of problem, because many of the values, like the 6 in both, cancel out. In fact, because we found that A/a = (2l/l)^2 we say in general that the area of a cube varies with the square of the length of its side.

I hope my answer has come to your help. Thank you for posting your question here in Brainly. We hope to answer more of your questions and inquiries soon. Have a nice day ahead!

4 0

4 years ago

What are the answers?

const2013 [10]

Answer:

Circle = 7

Pentagon = 8

Square = 12

Square + Square + Square = 36

Step-by-step explanation:

Since you know the circle is 7, the square plus the pentagon must be 20. That means the pentagon in the third equation is 8. This means the square is 12.

So, 12 + 12 + 12 = 36.

3 0

3 years ago

Read 2 more answers

an angles measure is 6 degrees more than 3 times the measure of its complwment. find the measure of the angles.

irina1246 [14]

Answer:

The angles are 22.5 and 67.5.

Step-by-step explanation:

A complement is the angle that when added to the given angle gives 90 degrees.

Therefore, the angle x is 3 times larger than its complement.

This means that x is 3/4 of 90 degrees and complement is 1/4 of 90 degrees.

Therefore, the angles are 22.5 and 67.5.

3 0

3 years ago

Jessica's heart beats 12 times in 1/6 minute how many times does her heart beat each minute

Charra [1.4K]

Answer:

72

Step-by-step explanation:

12 6 times equals 72.

12x6=72

4 0

4 years ago

The Wall Street Journal Corporate Perceptions Study 2011 surveyed readers and asked how each rated the Quality of Management and

kykrilka [37]

Answer:

The calculated χ² = 17.0281 falls in the critical region χ² ≥ 9.49 so we reject the null hypothesis that the quality of management and the reputation of the company are independent and conclude quality of management and the reputation of the company are dependent

The p-value is 0 .001909. The result is significant at p < 0.05

Part b:

40 > 8.5

35> 7.5

25> 4

Step-by-step explanation:

1) Let the null and alternative hypothesis as

H0: the quality of management and the reputation of the company are independent

against the claim

Ha: the quality of management and the reputation of the company are dependent

2) The significance level alpha is set at 0.05

3) The test statistic under H0 is

χ²= ∑ (o - e)²/ e where O is the observed and e is the expected frequency

which has an approximate chi square distribution with ( 3-1) (3-1)= 4 d.f

4) Computations:

Under H0 ,

Observed Expected E χ²= ∑(O-e)²/e

40 35.00 0.71

25 24.50 0.01

5 10.50 2.88

35 40.00 0.62

35 28.0 1.75

10 12.00 0.33

25 25.00 0.00

10 17.50 3.21

15 7.50 7.50

∑ 17.0281

Column Totals 100 70 30 200 (Grand Total)

5) The critical region is χ² ≥ χ² (0.05)2 = 9.49

6) Conclusion:

The calculated χ² = 17.0281 falls in the critical region χ² ≥ 9.49 so we reject the null hypothesis that the quality of management and the reputation of the company are independent and conclude quality of management and the reputation of the company are dependent.

7) The p-value is 0 .001909. The result is significant at p < 0.05

The p- values tells that the variables are dependent.

Part b:

If we take the excellent row total = 70 and compare it with the excellent column total= 100

If we take the good row total = 70 and compare it with the good column total= 80

If we take the fair row total = 50 and compare it with the fair column total= 30

The two attributes are said to be associated if

Thus we see that ( where (A)(B) are row and columns totals and AB are the cell contents)

AB> (A)(B)/N

40 > 1700/200

40 > 8.5

35> 1500/200

35> 7.5

25> 800/200

25> 4

and so on.

Hence they are positively associated

8 0

3 years ago