Answer:
-136
Step-by-step explanation:
We have to find the determinant of the following matrix:
![\left[\begin{array}{ccc}-4&5&6\\0&4&4\\-2&-5&4\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-4%265%266%5C%5C0%264%264%5C%5C-2%26-5%264%5Cend%7Barray%7D%5Cright%5D)
We can find the determinant by expanding via 1st column. i.e. by taking each element of 1st column and multiplying it by its co-factor matrix as shown below:
det ![\left[\begin{array}{ccc}-4&5&6\\0&4&4\\-2&-5&4\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-4%265%266%5C%5C0%264%264%5C%5C-2%26-5%264%5Cend%7Barray%7D%5Cright%5D)
= ![(-4 \times det \left[\begin{array}{cc}4&4\\-5&4\end{array}\right]) - (0 \times (-4 \times det \left[\begin{array}{cc}5&6\\-5&4\end{array}\right]))+ ((-2) \times det\left[\begin{array}{cc}5&6\\4&4\end{array}\right])\\\\ =-4 \times (16 + 20)-(0)+(-2 \times 20-24)\\\\ =-4(36)+(-2(-4))\\\\ =-144+8\\\\ =-136](https://tex.z-dn.net/?f=%28-4%20%5Ctimes%20det%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D4%264%5C%5C-5%264%5Cend%7Barray%7D%5Cright%5D%29%20-%20%280%20%5Ctimes%20%28-4%20%5Ctimes%20det%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D5%266%5C%5C-5%264%5Cend%7Barray%7D%5Cright%5D%29%29%2B%20%28%28-2%29%20%5Ctimes%20det%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D5%266%5C%5C4%264%5Cend%7Barray%7D%5Cright%5D%29%5C%5C%5C%5C%20%3D-4%20%5Ctimes%20%2816%20%2B%2020%29-%280%29%2B%28-2%20%5Ctimes%2020-24%29%5C%5C%5C%5C%20%3D-4%2836%29%2B%28-2%28-4%29%29%5C%5C%5C%5C%20%3D-144%2B8%5C%5C%5C%5C%20%3D-136)
The notation det() stands for determinant of the matrix.
Therefore, the determinant of the given matrix is -136
Answer:
a 2 x + 6
b 10 x - 20
c 8 x + 4
d 6 x - 24y
Step-by-step explanation:
Answer:
there is an economic principle that states that 1 dollar today is worth more than 1 dollar in the future, since an invested dollar could earn interests and gain value.
For example, we can assume a 6% interest rate (0.5% monthly interest rate), and using the present value formula we can determine the present value of $100:
- given to us in 30 days = $100 / (1 + 0.5%)¹ = $99.50
- given to us in 150 days = $100 / (1 + 0.5%)⁵ = $97.54
- given to us in 300 days = $100 / (1 + 0.5%)¹⁰ = $95.13
In order to calculate the value of $100 given to us tomorrow, we would need to determine a daily interest rate = 6% / 360 = 0.00017
- $100 given to us tomorrow = $100 / (1 + 0.00017)¹ = $99.98
since the amount of money is not that large and the interest rate is rather low, the difference in value is not that large. But imagine if you used a 24% interest rate instead of 6% (monthly interest rate = 2%)
- $100 given to us in 30 days = $100 / (1 + 2%)¹ = $98.04
- $100 given to us in 150 days = $100 / (1 + 2%)⁵ = $90.57
- $100 given to us in 300 days = $100 / (1 + 2%)¹⁰ = $82.03
as the interest rate increases, the present value decreases.
It’s 11 because -7 + 11 equals to 4.
-1/5, -4 I’m pretty sure and decimal form is -0.2, -4