Answer:
Step-by-step explanation:
![D =\left[\begin{array}{cc}8&-4\\-14&12\end{array}\right] -\left[\begin{array}{cc}-1&-15\\0&7\end{array}\right] \\\\\\\\=\left[\begin{array}{ccc}8+1&-4+15\\-14-0&12-7\end{array}\right]\\\\\\=\left[\begin{array}{ccc}9&11\\-14&5\end{array}\right]](https://tex.z-dn.net/?f=D%20%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D8%26-4%5C%5C-14%2612%5Cend%7Barray%7D%5Cright%5D%20-%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D-1%26-15%5C%5C0%267%5Cend%7Barray%7D%5Cright%5D%20%5C%5C%5C%5C%5C%5C%5C%5C%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D8%2B1%26-4%2B15%5C%5C-14-0%2612-7%5Cend%7Barray%7D%5Cright%5D%5C%5C%5C%5C%5C%5C%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D9%2611%5C%5C-14%265%5Cend%7Barray%7D%5Cright%5D)
Answer:
5/8
Step-by-step explanation:
Answer: 25 nickels
10 dimes
Step-by-step explanation:
Answer:
(-4,2)
Step-by-step explanation:
First we have to find a common multiple to use to add and find the system of equations. We need to eliminate one of the variables in order to solve.
Since 5 * 3 = 15, and 3 * -5 = 15, -15x and 15x will cancel each other out. Therefore x will be eliminated.
Before:
5x + 2y = -16
3x + 7y = 2
After:
15x + 6y = -48 <----------Now we solve for y
-15x + -35y = -10
+----------------------
-29y = -58
-29 -29
y = 2
Now what we do is we choose and equation and solve for x, since it is still unknown. Any equation is fine but I will choose the second one since it has easy numbers.
3x + 7y = 2
3x + 7(2) = 2
3x + 14 = 2
-14 -14
----------------------
3x = -12
3 3
x = -4
Therefore our final answer is (-4,2)
