Answer:
x= -2 and y= 8
Step-by-step explanation:
8x+5y=24-------A
y=-4x---------B
Putting the value of y from B in A
8x+5(-4x)=24
8x +(-20x)= 24
8x-20x=24
-12x=24
x= -24/12
x=-2--------C y =-4(-2)=8
$26.46
I divided 15.12 by 8 to get the cost of just one gallon , which was $1.89. 14 x 1.89 = 26.46, which would ideally be the cost to fill a 14-gallon tank.
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:
-3x+1y=-1
or
3x-1y=1
or
by multiplying with 1/3 the first equation we get
-1x+1/3y=-1/3
or from second equation
1x-1/3y=1/3
Step-by-step explanation:
y-y1=m(x-x1)
y1=-7
x1=-2
m=3
so
y-(-7)=3(x-(-2))
y+7=3(x+2)
y+7=3x+6
-3x+y=6-7
-3x+ 1y= -1
a triangle adds to 180 degrees
we have 90 and 40 so the hypotenuse is 50 degrees
