1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
sasho [114]
4 years ago
8

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

Mathematics
1 answer:
andriy [413]4 years ago
4 0
\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}
You might be interested in
January is almost over & it has been COLD! We discover that January is NATIONAL SOUP MONTH, so we're on a mission to finish
lidiya [134]
Simply just multiply 9 days by 3 meals by 2 people. it's 54
8 0
4 years ago
What is the equation of the quadratic graph with a focus of (1 ,3) and a directrix of y=1?
zimovet [89]
Check the picture below.

now, we know the directrix is at y = 1, and the focus point is at 1,3, well, notice the picture, the distance between those fellows is just 2 units.

the vertex is half-way between those fellows, therefore, the vertex will be at 1,2.

the distance "p", from the vertex to either the directrix or focus, is really just 1 unit.  Since the focus point is above the directrix, is a vertical parabola, and it opens upwards, like in the picture, and since it opens up, the "p" value is positive, or +1.

\bf \textit{parabola vertex form with focus point distance}\\\\
\begin{array}{llll}
4p(x- h)=(y- k)^2
\\\\
\boxed{4p(y- k)=(x- h)^2}
\end{array}
\qquad 
\begin{array}{llll}
vertex\ ( h, k)\\\\
 p=\textit{distance from vertex to }\\
\qquad \textit{ focus or directrix}
\end{array}\\\\
-------------------------------\\\\
\begin{cases}
h=1\\
k=2\\
p=1
\end{cases}\implies 4(1)(y-2)=(x-1)^2\implies 4(y-2)=(x-1)^2
\\\\\\
y-2=\cfrac{1}{4}(x-1)^2\implies y=\cfrac{1}{4}(x-1)^2+2

4 0
3 years ago
1/3 kilograms 2/3 what is the unit rate
storchak [24]
Idk I download this app so other ppl can help me
3 0
4 years ago
What is 2 + 10 x 30(7.7) - 2.34 x pi divided by 1/2 x 1.33333354 + 6(5 -6 x 10.10h)=?
yaroslaw [1]
The answer is 23209.0497168 + (5-6 x 10.10h) = ? 

sorry i cant help you anymore becuz i don't know what h is but i did simplify the other part for you so yeah 
7 0
3 years ago
What is the supplementary angle of 30 degrees?
Taya2010 [7]

Yawaaaaaaa HAHAHAHAHAHAHA

C ang anser ana hahahahahaha

5 0
3 years ago
Read 2 more answers
Other questions:
  • Mark but a brand new car for $35,000 in 2008 if the car depreciate in value approximately 8% per year write an exponential funct
    14·1 answer
  • 8. Solve the inequality –24 ≤ x – 3 – 8x. A. x ≥ 3 B. x ≥ –9 C. x ≤ 3 D. x ≥ –3
    15·2 answers
  • Jenya has 12 bills in her wallet. She has a total of $82. If she has twice as many $5 bill as $1 bills, and two more $10 bills t
    13·1 answer
  • PLEASE HELP
    6·1 answer
  • How do you solve 3(x-10)= -6 ?
    10·2 answers
  • The spinner below is spun. Find the probability,
    9·1 answer
  • 2 1/4 =1 2/7 ÷x<br><br> what is the value of x
    6·2 answers
  • You earned a 90% on a science test. You answered 36 questions correctly. How
    7·1 answer
  • Please help me with this homework using the substitution method
    6·1 answer
  • 200 POINTS! PLEASE HELP!!!
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!