The side walk in front of billys house is 9'8" long.how long is the side walk in inches

The floor and ceiling of a room represent planes that are _____

kicyunya [14]

They are parallel planes

4 0

3 years ago

Solve f(-4) for f(x) = 7x - 4x

Strike441 [17]

Answer:

-12

Step-by-step explanation:

What you have to do is plug -4 into the function as a puzzle. So, replace all x with -4.

f(-4) = 7(-4) - 4(-4) = -28 + 16 = -12

8 0

2 years ago

An independent-samples t test was conducted to compare high-altitude exercise to exercise at sea-level. Imagine the mean comfort

insens350 [35]

Answer:

-2.03, 2.03

Step-by-step explanation:

The degree of freedom (df) ;

Df total for the two samples = 35

Therefore, obtuaking the critical value using a T-test distribution at 95% confidence level.

(1 - 95%) / 2 = (1 - 0.95) / 2 = 0.05 / 2 = 0.025

Using a T critical value calculator or t table distribution ;

Tcritical, 0.025, df = 35 = 2.03

Left tail = - 2.03

Right = 2.03

Hence, critical cutoff :

(-2.03 ; 2.03)

7 0

3 years ago

Part of arianna’s earnings are based on a 5% commission rate. At the end of the day arianna earned 14.98 in commission. How much

Katarina [22]

Arianna sold for $ 299.6

Solution:

Given that, Part of Arianna’s earnings are based on a 5% commission rate

At the end of the day arianna earned 14.98 in commission

Therefore,

Commission earned = $ 14.98

Commission rate = 5 %

Let "x" be the amount that Arianna sell that day

Therefore, according to question,

5 % of amount earned = 14.98

5 % of "x" = 14.98

Solve the above equation for "x"

$5 \% \times x = 14.98\\\\\frac{5}{100} \times x = 14.98\\\\5x = 14.98 \times 100\\\\5x = 1498\\\\Divide\ both\ sides\ of\ equation\ by\ 5\\\\x = 299.6$

Thus arianna sold for $ 299.6

7 0

3 years ago

Suppose that v is an eigenvector of matrix A with eigenvalue λA, and it is also an eigenvector of matrix B with eigenvalue λB. (

galben [10]

Answer:

(a) Yes, $λ_{A}+λ_{B}$

(b) Yes, $λ_{A}λ_{B}$

Step-by-step explanation:

First, lets understand what are eigenvectors and eigenvalues?

Note: I am using the notation $λ_{A}$ to denote Lambda(A) sign.

$v$ is an eigenvector of matrix A with eigenvalue $λ_{A}$

$v$ is also eigenvector of matrix B with eigenvalue $λ_{B}$

So we can write this in equation form as

$Av=λ_{A}v$

So what does this equation say?

When you multiply any vector by A they do change their direction. any vector that is in the same direction as of $Av$ , then this $v$ is called the eigenvector of $A$ . $Av$ is $λ_{A}$ times the original $v$ . The number $λ_{A}$ is the eigenvalue of A.

$λ_{A}$ this number is very important and tells us what is happening when we multiply $Av$ . Is it shrinking or expanding or reversed or something else?

It tells us everything we need to know!

Bonus:

By the way you can find out the eigenvalue of $Av$ by using the following equation:

$det(A-λI)=0$

where I is identity matrix of the size of same as A.

Now lets come to the solution!

(a) Show that $v$ is an eigenvector of $A + B$ and find its associated eigenvalue.

The eigenvalues of $A$ and $B$ are $λ_{A}$ and $λ_{B}$ , then

$(A+B)(v)=Av+Bv=(λ_{A})v + (λ_{B})v=(λ_{A}+λ_{B})(v)$

so, $(A+B)(v)=(λ_{A}+λ_{B})(v)$

which means that $v$ is also an eigenvector of $A+B$ and the associated eigenvalues are $λ_{A}+λ_{B}$

(b) Show that $v$ is an eigenvector of $AB$ and find its associated eigenvalue.

The eigenvalues of $A$ and $B$ are $λ_{A}$ and $λ_{B}$ , then

$(AB)(v)=A(Bv)=A(λ_{B})=λ_{B}(Av)=λ_{B}λ_{A}(v)=λ_{A}λ_{B}(v)$

so,

$(AB)(v)=λ_{A}λ_{B}(v)$

which means that $v$ is also an eigenvector of $AB$ and the associated eigenvalues are $λ_{A}λ_{B}$

5 0

3 years ago