X² + x - 12 / x² - x - 20 ÷ 3x² - 24x + 45 / 12x² - 48x - 60
x² + x - 12 / x² - x - 20 * 12x² - 48x - 60 / 3x² - 24x + 45
<u>(x² + x - 12)(12x² - 48x - 60)</u>
(x² - x - 20)(3x² - 24x + 45)
<span><u>12x^4 - 48x³ - 60x² + 12x³ - 48x² - 60x - 144x² + 576x + 720</u>
</span>3x^4 - 24x³ + 45x² - 3x³ + 24x² - 45x - 60x² + 480x - 900
<span>
<u>12x^4 - 48x³ + 12x³ - 60x² - 48x² - 144x² - 60x + 576x + 720</u></span>
3x^4 - 24x³ - 3x³ + 45x² + 24x² - 60x² - 45x + 480x - 900
<u>12x^4 - 36x³ - 252x² + 516x + 720</u>
3x^4 - 27x³ + 9x² + 435x - 900
<u>12(x^4 - 3x³ - 21x² + 43x + 60) </u>
3(x^4 - 9x³ + 3x² + 145x + 300)
<u>4(</u><span><u>x^4 - 3x³ - 21x² + 43x + 60) </u>
</span><span> (x^4 - 9x³ + 3x² + 145x + 300)</span>
Answer: The system of equations is:
x + 2y + 2 = 4
y - 3z = 9
z = - 2
The solution is: x = -22; y = 15; z = -2;
Step-by-step explanation: ONe way of solving a system of equations is using the Gauss-Jordan Elimination.
The method consists in transforming the system into an augmented matrix, which is writing the system in form of a matrix and then into a <u>Row</u> <u>Echelon</u> <u>Form,</u> which satisfies the following conditions:
- There is a row of all zeros at the bottom of the matrix;
- The first non-zero element of any row is 1, which called leading role;
- The leading row of the first row is to the right of the leading role of the previous row;
For this question, the matrix is a Row Echelon Form and is written as:
![\left[\begin{array}{ccc}1&2&2\\0&1&3\\0&0&1\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D1%262%262%5C%5C0%261%263%5C%5C0%260%261%5Cend%7Barray%7D%5Cright%5D)
![\left[\begin{array}{ccc}4\\9\\-2\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D4%5C%5C9%5C%5C-2%5Cend%7Barray%7D%5Cright%5D)
or in system form:
x + 2y + 2z = 4
y + 3z = 9
z = -2
Now, to determine the variables:
z = -2
y + 3(-2) = 9
y = 15
x + 30 - 4 = 4
x = - 22
The solution is (-22,15,-2).
20% of 75 = 15
75 - 15 = £60
It should be c) £60
Answer:
15/56
Step-by-step explanation: