Answer:
D
Step-by-step explanation:
4 x^ + 36=0
4x( x + 9) =0 provd
ANSWER
24
EXPLANATION
For a matrix A of order n×n, the cofactor
of element
is defined to be

is the minor of element
equal to the determinant of the matrix we get by taking matrix A and deleting row i and column j.
Here, we have

M₁₁ is the determinant of the matrix that is matrix A with row 1 and column 1 removed. The bold entries are the row and the column we delete.

Since the determinant of a 2×2 matrix is

it follows that

so 
Answer:
charges for the first hour = $7.55
charges for each additional hour = $1.55
c = 1.55h + 7.55
Step-by-step explanation:
Let
x = charges for the first hour
y = charges for each additional hour
x + 2y = 10.65 (1)
x + 5y = 15.30 (2)
Subtract (1) from (2)
5y - 2y = 15.30 - 10.65
3y = 4.65
y = 4.65/3
= 1.55
y = $1.55
Substitute y = 1.55 into
x + 2y = 10.65
x + 2(1.55) = 10.65
x + 3.10 = 10.65
x = 10.65 - 3.10
= 7.55
x = $7.55
c = 1.55h + 7.55
12 to 16 pounds Im not very good at math but I hope this helps