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3 years ago

Use any method to solve the equation. If necessary, round to the nearest hundredth. 9x^2-21=0

Mathematics

1 answer:

zavuch27 [327]3 years ago

7 0

Answer:

x = 1.53, -1.53.

Step-by-step explanation:

9x^2 - 21 = 0

9x^2 = 21

x^2 = 21/9

x = +/- √21 / 3

x = 1.53, -1.53.

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Refer to the accompanying TI-83/84 Plus calculator display of a 95% confidence interval. The sample display results from using a

nikklg [1K]

Answer:

The confidence interval is $22.805$

Step-by-step explanation:

We have given,

The Z interval (23.305,25.075)

Mean $\bar{x}=23.69$

Sample n=30

To find : The confidence interval?

Solution :

We know, The confidence interval is in the format of

$\bar{x}-E$

E denotes the margin of error,

$E=\frac{U-L}{2}$

Where, U is the upper limit U=25.075

L is the lower limit L=23.305

$E=\frac{25.075-23.305}{2}$

$E=\frac{1.77}{2}$

$E=0.885$

Substitute the value of E and $\bar{x}$ in the formula,

$23.69-0.885$

$22.805$

Therefore, The confidence interval is $22.805$

8 0

4 years ago

Find the measure of angle ABC

victus00 [196]

First we need to find x so 6x+8x+6x= 180
20x=180 and x= 9

So A= 6*9= 54
B= 8*9= 72
C= 6*9= 54

5 0

3 years ago

Identify intervals on which the function is increasing, decreasing, or constant.

tigry1 [53]

G ( x ) = 2 - ( x - 7 )²
g ( x ) = 2 - ( x² - 14 x + 49 )
g ( x ) = 2 - x² + 14 x - 49
g ( x ) = - x² + 14 x - 47
The maximum of the function is at:
x= - b / 2 a
x = - 14 / ( - 2 ) = 7
Therefore the function is increasing form x ∈ ( - ∞, 7 ) and decreasing for x ∈ ( 7, +∞ ).
Answer:
C. increasing, x < 7; decreasing x > 7.

3 0

3 years ago

What is the HCF of 20 36 and 45??

tangare [24]

20=1×2×2×5=1×4×5

36=1×2×2×9=1×4×9

45=1×3×3×5=1×9×5[/tex]