Answer:
f(x) = -5x - 4
Step-by-step explanation:
We want to get the inverse of the following function:
f^-1(x) = (-1/5)x - 4/5
To do that, we have to replace x with f(x) and f^-1(x) with x, as follows:
x = (-1/5)f(x) - 4/5
And then solve for f(x), the inverse of f^-1(x).
x + 4/5 = (-1/5)f(x)
f(x) = -5x + (-5)4/5
f(x) = -5x - 4
To check our result we compute a pair (x, f(x))
x f(x)
1 -5*1 - 4 = -9
which has to be equivalent to (-9, 1) in the original function
x f^-1(x)
-9 (-1/5)*(-9) - 4/5 = 1
Answer:
18
Step-by-step explanation:
Answer:
Chelsea spent more than $12.75
Step-by-step explanation:
To solve this problem we should understand the meaning of signs first.
sign (<) → less than
sign (>) → more than
sign (=) → equal to
sign (≤) → Not more than
sign (≥) → At least
If the statement is,
"Chelsea spent more than $12.75"
d > 12.75
Therefore, Chelsea spent more than $12.75 is the correct statement.
Answer:
333.33
Step-by-step explanation:
x is directly proportional to y
k=y/x
k=3/200
now,
when y =5
y=kx
5=(3/200)x
1000/3=x
333.33 = x
Answer:
n times 5
Step-by-step explanation:
A matrix Anxn of this way is called an upper triangular matrix. It can be proved that the determinant of this kind of matrix is

In this case, it would be 5+5+...+5 (n times) = n times 5
We are going to develop each determinant by the first column taking as pivot points the elements of the diagonal
![det\left[\begin{array}{cccc}5&a_{12}&a_{13}...&a_{1n}\\0&5&a_{23}...&a_{2n}\\...&...&...&...\\0&0&0&5\end{array}\right] =5+det\left[\begin{array}{ccc}5&a_{23}...&a_{2n}\\0&5&a_{3n}\\...&...&...\\0&0&5\end{array}\right]=5+5+...+det\left[\begin{array}{cc}5&a_{n-1,n}\\0&5\end{array}\right]=5+5+...+5+5\;(n\;times)](https://tex.z-dn.net/?f=det%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D5%26a_%7B12%7D%26a_%7B13%7D...%26a_%7B1n%7D%5C%5C0%265%26a_%7B23%7D...%26a_%7B2n%7D%5C%5C...%26...%26...%26...%5C%5C0%260%260%265%5Cend%7Barray%7D%5Cright%5D%20%3D5%2Bdet%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D5%26a_%7B23%7D...%26a_%7B2n%7D%5C%5C0%265%26a_%7B3n%7D%5C%5C...%26...%26...%5C%5C0%260%265%5Cend%7Barray%7D%5Cright%5D%3D5%2B5%2B...%2Bdet%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D5%26a_%7Bn-1%2Cn%7D%5C%5C0%265%5Cend%7Barray%7D%5Cright%5D%3D5%2B5%2B...%2B5%2B5%5C%3B%28n%5C%3Btimes%29)