ABC Bookstore sells one customer 12 used books and 4 new books for $136.

Mathematics

1 answer:

Natalka [10]2 years ago

5 0

Answer:

n=6 u=28/3

Step-by-step explanation:

system of equations

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Come someone please help me and explain this

OLga [1]

Change in y over change in x

7 0

3 years ago

If you answer my question can you please tell me how to do it step by step.

hichkok12 [17]

Answer:

Depends

Step-by-step explanation:

It depends because I don't know if I'm strong on the material you're asking about.

5 0

3 years ago

Which of the following is the vertical asymptote for the graph below?

forsale [732]

Answer:

Step-by-step explanation:

Vertical asymptotes are always in the form x = ?

If you look at the dotted line, it lands on 2. Because it's a vertical line, the asymptote is going to be x = 2

4 0

2 years ago

Use Cramer’s rule to solve for x: x + 4y − z = −14 5x + 6y + 3z = 4 −2x + 7y + 2z = −17

V125BC [204]

Looks like the system is

x + 4y - z = -14

5x + 6y + 3z = 4

-2x + 7y + 2z = -17

or in matrix form,

$\mathbf{Ax} = \mathbf b \iff \begin{bmatrix} 1 & 4 & -1 \\ 5 & 6 & 3 \\ -2 & 7 & 2 \end{bmatrix} \begin{bmatrix} x \\ y \\ z \end{bmatrix} = \begin{bmatrix} -14 \\ 4 \\ -17 \end{bmatrix}$

Cramer's rule says that

$x_i = \dfrac{\det \mathbf A_i}{\det \mathbf A}$

where $x_i$ is the solution for i-th variable, and $\mathbf A_i$ is a modified version of $\mathbf A$ with its i-th column replaced by $\mathbf b$ .

We have 4 determinants to compute. I'll show the work for det(A) using a cofactor expansion along the first row.

$\det \mathbf A = \begin{vmatrix} 1 & 4 & -1 \\ 5 & 6 & 3 \\ -2 & 7 & 2 \end{vmatrix}$

$\det \mathbf A = \begin{vmatrix} 6 & 3 \\ 7 & 2 \end{vmatrix} - 4 \begin{vmatrix} 5 & 3 \\ -2 & 2 \end{vmatrix} - \begin{vmatrix} 5 & 6 \\ -2 & 7 \end{vmatrix}$