Answer:
Solution : (15, - 11)
Step-by-step explanation:
We want to solve this problem using a matrix, so it would be wise to apply Gaussian elimination. Doing so we can start by writing out the matrix of the coefficients, and the solutions ( - 5 and - 2 ) --- ( 1 )

Now let's begin by canceling the leading coefficient in each row, reaching row echelon form, as we desire --- ( 2 )
Row Echelon Form :

Step # 1 : Swap the first and second matrix rows,

Step # 2 : Cancel leading coefficient in row 2 through
,

Now we can continue canceling the leading coefficient in each row, and finally reach the following matrix.

As you can see our solution is x = 15, y = - 11 or (15, - 11).
Answer: What is a factor?
A factor is a a divisor of an integer n, also called a factor of n, is an integer m that may be multiplied by some integer to produce n. In this case, one also says that n is a multiple of m. An integer n is divisible by another integer m if m is a divisor of n; this implies dividing n by m leaves no remainder.
Step-by-step explanation: Why can’t certain expressions be factored?
Because there are no common factors other than 1 the constants cannot be factored. And, because there is no x in the second term (10), we cannot factor an x out of the two terms.
Answer:
The quotient is: x-7
and remainder is : -300
Step-by-step explanation:
We need to divide
by 
First arrange the term
in terms of ascending order of x.
Arranging we get:
\ 
The division steps are shown in figure attached.
The quotient is: x-7
and remainder is : -300
Answer:
x = 6
Step-by-step explanation:
8x + 2 + 70 + 60 = 180
8x + 132 = 180
8x = 48
x = 6
it is 20 minuets that she went over on her bill