All categories

2 years ago

What’s the value of x

Mathematics

1 answer:

stiks02 [169]2 years ago

4 0

Answer:

Step-by-step explanation:

Pythagorean theorem:

x² + x² = (9√2)²

2x² = 162

x² = 81

x = 9

You might be interested in

Suppose a bag contains 7 blue chips ad 3 gold chips.What is the probability of randomly choosing a gold chip,not replacing it,an

castortr0y [4]

$|\Omega|=10\cdot9=90\\ |A|=3\cdot2=6\\\\ P(A)=\dfrac{6}{90}=\dfrac{1}{15}\approx7\%$

6 0

3 years ago

Claim: The standard deviation of pulse rates of adult males is less than 11 bpm. For a random sample of 132 adult males, the pu

seraphim [82]

Answer:

$\chi^2 =\frac{132-1}{121} 114.49 =123.952$

Step-by-step explanation:

Notation and previous concepts

A chi-square test is "used to test if the variance of a population is equal to a specified value. This test can be either a two-sided test or a one-sided test. The two-sided version tests against the alternative that the true variance is either less than or greater than the specified value"

$n=132$ represent the sample size

$\alpha$ represent the confidence level

$s^2 =10.7^2 =114.49$ represent the sample variance obtained

$\sigma^2_0 =11^2=121$ represent the value that we want to test

Null and alternative hypothesis

On this case we want to check if the population variance specification is violated, so the system of hypothesis would be:

Null Hypothesis: $\sigma^2 \geq 121$

Alternative hypothesis: $\sigma^2$

Calculate the statistic

For this test we can use the following statistic:

$\chi^2 =\frac{n-1}{\sigma^2_0} s^2$

And this statistic is distributed chi square with n-1 degrees of freedom. We have eveything to replace.

$\chi^2 =\frac{132-1}{121} 114.49 =123.952$

Calculate the p value

In order to calculate the p value we need to have in count the degrees of freedom , on this case 131. And since is a right tailed test the p value would be given by:

$p_v =P(\chi^2$

In order to find the p value we can use the following code in excel:

"=1-CHISQ.DIST(123.952,131,TRUE)"

5 0

3 years ago

Is -2(3x-7) equivalent to 19+12x-5-6x? YES or NO???

nadezda [96]

Answer:

6. 6x-21=33+9x 7. -15x=-5(3x+7) 8. 16x-19=113-6x 9. -19x-34=56-x 10. -6(4x+3)=6(4x-3)?

6. 6x-21 = 33 +9x

+21 + 21

6x = 54 + 9x

-9x -9x

-3x = 54

/3 /3

x = -18

7. -15x = -5(3x+7)

First multiply the -5 to the other numbers.

-15x = -15x - 35

0x = -35

7 is impossible I believe.

8. 16x-19 = 113-6x

+6 +6

22x - 19 = 113

+ 19 +19

22x = 132

/22 /22

x = 6

9. -19x - 34 = 56 - x

+19x +19x

-34 = 56 + 18x

-56 -56

-90 = 18x

/18 /18

x = -5

10. -6(4x+3) = 6[4x-3]

-24x - 18 = 24x - 18

+18 +18

-24x= 24x

x = 0, since only zero can make the equation true.

7 0

3 years ago

Find the sum of a finite geometric sequence from n = 1 to n = 7, using the expression −4(6)n − 1.

Verizon [17]

Answer:

Step-by-step explanation:

The formula of a sum of terms of a gometric sequence:

$S_n=a_1\cdot\dfrac{1-r^n}{1-r}$

a₁ - first term

r - common ratio

We have

$a_n=-4(6)^{n-1}$

Calculate a₁. Put n = 1:

$a_1=-4(6)^{1-1}=-4(6)^0=-4(1)=-4$

Calculate the common ratio:

$r=\dfrac{a_{n+1}}{a_n}\\\\a_{n+1}=-4(6)^{n+1-1}=-4(6)^n\\\\r=\dfrac{-4(6)^n}{-4(6)^{n-1}}=6^n:6^{n-1}\\\\\text{use}\ a^n:a^m=a^{n-m}\\\\r=6^{n-(n-1)}=6^{n-n+1}=6^1=6$

$\text{Substitute}\ a_1=-4,\ n=7,\ r=6:\\\\S_7=-4\cdot\dfrac{1-6^7}{1-6}=-4\cdot\dfrac{1-279936}{-5}=-4\cdot\dfrac{-279935}{-5}=(-4)(55987)\\\\S_7=-223948$

7 0

3 years ago

What is the ratio of 4 shirts for 32.00what is the ratio and percent of 4 shirts for 32.00

kap26 [50]

Answer: each shirt is 8 dollars so for every 1 there is 8 tje percent would be 25% = 1 shirt or $8.00 Hope this helps!

Step-by-step explanation:

6 0

3 years ago