Answer:
![\left[\begin{array}{ccc}5&7\\5&-8\\3&-9\end{array}\right] \left[\begin{array}{ccc}c\\d\end{array}\right] =\left[\begin{array}{ccc}-16\\3\\-15\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D5%267%5C%5C5%26-8%5C%5C3%26-9%5Cend%7Barray%7D%5Cright%5D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Dc%5C%5Cd%5Cend%7Barray%7D%5Cright%5D%20%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-16%5C%5C3%5C%5C-15%5Cend%7Barray%7D%5Cright%5D)
This tells us that:
![A=\left[\begin{array}{ccc}5&7\\5&-8\\3&-9\end{array}\right]](https://tex.z-dn.net/?f=A%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D5%267%5C%5C5%26-8%5C%5C3%26-9%5Cend%7Barray%7D%5Cright%5D)
![b=\left[\begin{array}{ccc}-16\\3\\-15\end{array}\right]](https://tex.z-dn.net/?f=b%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-16%5C%5C3%5C%5C-15%5Cend%7Barray%7D%5Cright%5D)
Step-by-step explanation:
So we are saying we have scalars, c and d, such that:
![c\left[\begin{array}{ccc}5\\5\\ 3\end{array}\right]+d\left[\begin{array}{ccc}7\\-8\\-9\end{array}\right]=\left[\begin{array}{ccc}-16\\3\\-15\end{array}\right]](https://tex.z-dn.net/?f=c%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D5%5C%5C5%5C%5C%203%5Cend%7Barray%7D%5Cright%5D%2Bd%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D7%5C%5C-8%5C%5C-9%5Cend%7Barray%7D%5Cright%5D%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-16%5C%5C3%5C%5C-15%5Cend%7Barray%7D%5Cright%5D)
.
So we want to find a way to express this as:
Ax=b where x is the scalar vector, ![\left[\begin{array}{ccc}c\\d\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Dc%5C%5Cd%5Cend%7Barray%7D%5Cright%5D)
.
So we can write this as:
It will be c- 20:
4q and 2(q+30) have to equal the same therefore q=30 which makes both these equations equal.
3p + 4q then have to equal 180 as they are on a straight line so you know q=30 so 4x30=120 so 180-120=60
Then 60/3=20 and that is your answer.
Hope this helps :)
Complete the square
first isolate x terms
y=(x^2-4x)-9
complete square inside (take 1/2 of square of b )
-4/2=-2, (-2)^2=4
add 4-4 inside
y=(x^2-4x+4-4)-9
complete the square
y=((x-2)^2-4)-9
y=(x-2)^2-4-9
y=(x-2)^2-13
Answer:
39.46
Step-by-step explanation:
