Does this matrix have an inverse?why or why not ?

(3x3 + 2x2 − 5x) − (8x3 − 2x2).

uranmaximum [27]

My answer -

-5x^3+4x^2-5x

P.S

Have an AWESOME!!! LBGT Day :)

3 0

4 years ago

Read 2 more answers

SOMEONE PLSLPLSSLSLS HELP ITS JUST 3 QUESTIONS BRO PLEASE ITS SO CONFUSING ILL BRAINLIST.

Vinil7 [7]

Step-by-step explanation:

a) Perimeter is equal to 2w + 2L

2(3x + 4) + 2(x + 3)

6x + 8 + 2x + 6

8x + 14

b) Put 5 in x's place

8×5 + 14

40 + 14

54

c) Area = (3x + 4) * (x + 3)

Put 4 in x's place

(3×4 + 4) * (4 + 3)

12 + 4 * 7

16 * 7

112

5 0

2 years ago

The mean time required to repair breakdowns of a certain copying machine is 93 minutes. The company which manufactures the machi

Sonja [21]

Answer:

$t=\frac{88.8-93}{\frac{26.6}{\sqrt{73}}}=-1.349$

$p_v =P(t_{(72)}$

If we compare the p value and the significance level given $\alpha=0.05$ we see that $p_v>\alpha$ so we can conclude that we have enough evidence to fail reject the null hypothesis, and we can't concluce that the true mean is less than 93 min at 5% of signficance.

Step-by-step explanation:

Data given and notation

$\bar X=88.8$ represent the sample mean

$s=26.6$ represent the sample standard deviation for the sample

$n=73$ sample size

$\mu_o =93$ represent the value that we want to test

$\alpha=0.05$ represent the significance level for the hypothesis test.

t would represent the statistic (variable of interest)

$p_v$ represent the p value for the test (variable of interest)

State the null and alternative hypotheses.

We need to conduct a hypothesis in order to check if the true mean i lower than 93 min, the system of hypothesis would be:

Null hypothesis: $\mu \geq 93$

Alternative hypothesis: $\mu < 93$

If we analyze the size for the sample is > 30 but we don't know the population deviation so is better apply a t test to compare the actual mean to the reference value, and the statistic is given by:

$t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}}$ (1)

t-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

Calculate the statistic

We can replace in formula (1) the info given like this:

$t=\frac{88.8-93}{\frac{26.6}{\sqrt{73}}}=-1.349$

P-value

The first step is calculate the degrees of freedom, on this case:

$df=n-1=73-1=72$

Since is a one side test the p value would be:

$p_v =P(t_{(72)}$

Conclusion

If we compare the p value and the significance level given $\alpha=0.05$ we see that $p_v>\alpha$ so we can conclude that we have enough evidence to fail reject the null hypothesis, and we can't concluce that the true mean is less than 93 min at 5% of signficance.

5 0

3 years ago

In Tayshia's pantry, there are bags of Cheetos and Doritos. The ratio of Cheetos to total bags of chips in her pantry is 9 to 16

erma4kov [3.2K]

It’s not enough information given

7 0

3 years ago

If a dart was thrown randomly at the dart board shown below, what is the probability that it would land between the outer circle

Mademuasel [1]

Answer: B) 67%

<u>Step-by-step explanation:</u>

Find the Area of the Bullseye and Middle ring

A = π r²

A (inside) = π(8)² = 64π

Find the Area of the entire Target

A (target) = π (14)² = 196π

Find the Area of the Outer ring

A (outer ring) = A (target) - A(inside)

= 196 π - 64π

= 132 π

The last step is to find the probability of landing on the outer ring:

$P=\dfrac{success (area\ of\ outer\ ring)}{total\ possible\ outcomes(area\ of\ target)}=\dfrac{132\pi}{196\pi}=0.673=\large\boxed{67\%}$

7 0

3 years ago