Answer:
Step-by-step explanation:
We have the following system
![\left[\begin{matrix} 4 & -2 \\ 2 & 1 \end{matrix}\right]x =\left[\begin{matrix} 8 \\ 2 \end{matrix}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Bmatrix%7D%204%20%26%20-2%20%5C%5C%202%20%26%201%20%5Cend%7Bmatrix%7D%5Cright%5Dx%20%3D%5Cleft%5B%5Cbegin%7Bmatrix%7D%208%20%5C%5C%202%20%5Cend%7Bmatrix%7D%5Cright%5D)
The number of solutions depend on the determinant of the matrix of the system. If the determinant is different from 0, then it has one unique solution, if it 0 then it has infinite solutions.
Note that the determinant of a matrix
![\left[\begin{matrix} a & b \\ c & d \end{matrix}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Bmatrix%7D%20a%20%26%20b%20%5C%5C%20c%20%26%20d%20%5Cend%7Bmatrix%7D%5Cright%5D)
is ad-bc. So in our case we have 4*1-(-2)*2 = 8 which is not 0. Then the system has an unique solution.
Answer:
Step-by-step explanation:
Let x be the price of the breakfast.
We know that 20 percent of x is 1.80
Let's write this as a mathematical equation
0.2 x = 1.8
Let's divide both sides by 0.2 to isolate the x
x = 1.8 / 0.2
= 9
The price of the breakfast was $9.
Have an awesome day! :)
1X0.28
dude thats easy man
Answer:
76°
Step-by-step explanation:
The opposite angles of a parallelogram are equal, so if one angle is 76°, then the opposite angle will be the same.
I hope this helps!
