The coefficient matrix is build with its rows representing each equation, and its columns representing each variable.
So, you may write the matrix as
![\left[\begin{array}{cc}\text{x-coefficient, 1st equation}&\text{y-coefficient, 1st equation}\\\text{x-coefficient, 2nd equation}&\text{y-coefficient, 2nd equation} \end{array}\right]](https://tex.z-dn.net/?f=%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D%5Ctext%7Bx-coefficient%2C%201st%20equation%7D%26%5Ctext%7By-coefficient%2C%201st%20equation%7D%5C%5C%5Ctext%7Bx-coefficient%2C%202nd%20equation%7D%26%5Ctext%7By-coefficient%2C%202nd%20equation%7D%20%5Cend%7Barray%7D%5Cright%5D%20%20)
which means
![\left[\begin{array}{cc}4&-3\\8&-3\end{array}\right]](https://tex.z-dn.net/?f=%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D4%26-3%5C%5C8%26-3%5Cend%7Barray%7D%5Cright%5D%20%20)
The determinant is computed subtracting diagonals:
![\left | \left[ \begin{array}{cc}a&b\\c&d\end{array}\right]\right | = ad-bc](https://tex.z-dn.net/?f=%20%5Cleft%20%7C%20%5Cleft%5B%20%5Cbegin%7Barray%7D%7Bcc%7Da%26b%5C%5Cc%26d%5Cend%7Barray%7D%5Cright%5D%5Cright%20%7C%20%3D%20ad-bc%20)
So, we have
![\left | \left[\begin{array}{cc}4&-3\\8&-3\end{array}\right] \right | = 4(-3) - 8(-3) = -4(-3) = 12](https://tex.z-dn.net/?f=%20%5Cleft%20%7C%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D4%26-3%5C%5C8%26-3%5Cend%7Barray%7D%5Cright%5D%20%5Cright%20%7C%20%3D%204%28-3%29%20-%208%28-3%29%20%3D%20-4%28-3%29%20%3D%2012%20%20)
Answer:
SA=571.77
Step-by-step explanation:
SA==2πrh+2πr2=2·π·7·6+2·π·72≈571.76986
pls mark brainliest
He ran 14 km, multiply 6 by 2 and 1/3.
<span>Simplifying
0x + 7 + 5x = 2x + 30 + 40
Anything times zero is zero.
0x + 7 + 5x = 2x + 30 + 40
Combine like terms: 0 + 7 = 7
7 + 5x = 2x + 30 + 40
Reorder the terms:
7 + 5x = 30 + 40 + 2x
Combine like terms: 30 + 40 = 70
7 + 5x = 70 + 2x
Solving
7 + 5x = 70 + 2x
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '-2x' to each side of the equation.
7 + 5x + -2x = 70 + 2x + -2x
Combine like terms: 5x + -2x = 3x
7 + 3x = 70 + 2x + -2x
Combine like terms: 2x + -2x = 0
7 + 3x = 70 + 0
7 + 3x = 70
Add '-7' to each side of the equation.
7 + -7 + 3x = 70 + -7
Combine like terms: 7 + -7 = 0
0 + 3x = 70 + -7
3x = 70 + -7
Combine like terms: 70 + -7 = 63
3x = 63
Divide each side by '3'.
x = 21
Simplifying
x = 21</span>
Answer:
To determine whether a decimal is rational or not, you need to know that...
Irrational numbers don't end and have no pattern whereas rational numbers are the complete opposite. Rational numbers end and have a repeating pattern.
Step-by-step explanation:
Here are examples of irrational numbers:
0.9384903204..... , π , √2
Examples of rational numbers:
0.777777... (is rational because it has a repeating pattern of 7) , √49
Hope this helps :)
