Answer:
(x +4)^2 -45
Step-by-step explanation:
The square of a binomial has the form ...
(x +a)^2 = x^2 +2ax +a^2
That is, the constant term (a^2) is the square of half the coefficient of the linear term: (2a/2)^2 = a^2.
To "complete the square", you add 0 in the form of the desired constant added to its opposite. Here, we want the constant for the square to be (8/2)^2 = 16. So, we can add 0 = 16 -16 to the expression:
x^2 +8x +16 -29 -16
(x^2 +8x +16) -45 . . . . group the terms that make the square
(x +4)^2 -45 . . . . rewritten after completing the square
Answer:
Toby will reach more people in 40 phone calls
<h3>
Answer:</h3>
(x, y) = (7, -5)
<h3>
Step-by-step explanation:</h3>
It generally works well to follow directions.
The matrix of coefficients is ...
![\left[\begin{array}{cc}2&4\\-5&3\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D2%264%5C%5C-5%263%5Cend%7Barray%7D%5Cright%5D)
Its inverse is the transpose of the cofactor matrix, divided by the determinant. That is ...
![\dfrac{1}{26}\left[\begin{array}{ccc}3&-4\\5&2\end{array}\right]](https://tex.z-dn.net/?f=%5Cdfrac%7B1%7D%7B26%7D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D3%26-4%5C%5C5%262%5Cend%7Barray%7D%5Cright%5D)
So the solution is the product of this and the vector of constants [-6, -50]. That product is ...
... x = (3·(-6) +(-4)(-50))/26 = 7
... y = (5·(-6) +2·(-50))/26 = -5
The solution using inverse matrices is ...
... (x, y) = (7, -5)
Answer:
idk
Step-by-step explanation: