D
given the 2 equations
x + 2y = - 8 → (1)
- 4x + y = 5 → (2)
multiply (1) by 4
4x + 8y = - 32 → (3)
add (2) and (3) term by term to eliminate term in x
9y = - 27 ( divide both sides by 9 )
y = - 3
substitute y = - 3 in either (1) or (2) and solve for x
(1) : x - 6 = - 8 ( add 6 to both sides )
x = - 2
solution is (- 2, - 3 ) → D
Ordered pair is simply the solution to a system of equation.
The solution is: (d) (-2,-3)
The equations are given as:
[tex]\mathbf{x + 2y = -8}[/tex]
[tex]\mathbf{-4x + y = 5}[/tex]
Make x the subject in [tex]\mathbf{x + 2y = -8}[/tex]
[tex]\mathbf{x = -8 - 2y}[/tex]
Substitute [tex]\mathbf{x = -8 - 2y}[/tex] in [tex]\mathbf{-4x + y = 5}[/tex]
[tex]\mathbf{-4(-8 - 2y) + y = 5}[/tex]
Open brackets
[tex]\mathbf{32 + 8y + y = 5}[/tex]
[tex]\mathbf{32 + 9y = 5}[/tex]
Subtract 32 from both sides
[tex]\mathbf{9y = -27}[/tex]
Divide both sides by 9
[tex]\mathbf{y = -3}[/tex]
Substitute [tex]\mathbf{y = -3}[/tex] in [tex]\mathbf{x = -8 - 2y}[/tex]
[tex]\mathbf{x = -8 - 2(-3)}[/tex]
[tex]\mathbf{x = -8 +6}[/tex]
[tex]\mathbf{x = -2}[/tex]
Hence, the solution is: (-2,-3)
Read more about ordered pairs at:
https://brainly.com/question/6585011
