Can someone help me with this question

Use Cramer's Rule to solve the following system: –2x – 6y = –26 5x + 2y = 13

andriy [413]

$\bf \begin{cases}
-2x-6y&=-26\\
\quad 5x+2y&=13
\end{cases}\stackrel{\textit{determinant of the coefficients}}{D=
\begin{bmatrix}
-2&-6\\5&2
\end{bmatrix}}\implies (-4)-(-30)
\\\\\\
D=-4+30\implies \boxed{D=26}\\\\
-------------------------------\\\\$

$\bf x=\cfrac{D_x}{D}\implies x=\cfrac{
\begin{bmatrix}
\boxed{-26}&-6\\\\ \boxed{13}&2
\end{bmatrix}}{D}\implies x=\cfrac{(-52)-(-78)}{26}
\\\\\\
x=\cfrac{-52+78}{26}\implies x=\cfrac{26}{26}\implies \boxed{x=1}\\\\
-------------------------------\\\\
y=\cfrac{D_y}{D}\implies y=\cfrac{
\begin{bmatrix}
-2&\boxed{-26}\\\\ 5&\boxed{13}
\end{bmatrix}}{D}\implies y=\cfrac{(-26)-(-130)}{26}
\\\\\\
y=\cfrac{-26+130}{26}\implies y=\cfrac{104}{26}\implies \boxed{y=4}$

4 0

3 years ago

3. A boy mixed 500g of sugar and 120g of salt in 106g of lime juice. What will be the

Fed [463]

Answer:

Option C...726 g

Step-by-step explanation:

Mass of;

sugar = 500g

salt = 120g

lime juice = 106g

mass of mixture = sum of its components

= 500g + 120g + 106g

=726 g

6 0

2 years ago

What is the vertex of the graph of the function f(x) = 2(x − 2)2 + 3? Enter your answer in the boxes.

Pani-rosa [81]

Answer:

The vertex of the function is at (2,3).

Step-by-step explanation:

I graphed the equation on the graph below.

If this answer is correct, please make me Brainliest!

3 0

3 years ago

Oregon State University is interested in determining the average amount of paper, in sheets, that is recycled each month. In pre

Juliette [100K]

Answer:

The test statistic is $t = 2.79$

Step-by-step explanation:

From the question we are told that

The population mean is $\mu = 59.3$

The sample size is $n = 79$

The sample mean is $\= x = 62.4$

The standard deviation is $\sigma = 9.86$

Generally the test statistics is mathematically represented as

$t = \frac{\= x - \mu }{ \frac{ \sigma}{ \sqrt{n} } }$

substituting values

$t = \frac{ 62.2 - 59.3 }{ \frac{ 9.86}{ \sqrt{ 79} } }$

$t = 2.79$

4 0

3 years ago

How are piecewise functions and infinite limits alike? How are they different?

Shtirlitz [24]

Answer: i got 100% on the journal activity on EDGE with this “ The difference of piecewise functions and infinite limits is the graphs, with piecewise functions you're graphing several equations... when looking at a graph with an infinite limit there is a difference. A similarity they do have is their end points.” I haven’t been paying attention at all so this I made this up and some how it works(?!)

Step-by-step explanation: I’m not sure if it’s even correct but it worked as a response!

3 0

3 years ago