Respuesta :
Answer:
(x, y ) = (3 , - 4 )
Step-by-step explanation:
given the 2 equations
2x - 3y = 18 → (1)
4x + y = 8 → (2)
multiply (2) by 3
12x + 3y = 24 → (3)
add (1) and (3) term by term to eliminate the term in y
(2x + 12x) + (- 3y + 3y) = (18 + 24)
14x = 42 ( divide both sides by 14 )
x = 3
substitute x = 3 in (1) or (2) to evaluate for y-coordinate
(2) → 12 + y = 8 ⇒ y = 8 - 12 = - 4
solution is (3, - 4 )
2x - 3y = 18
4x + y = 8
/*multiply first eqtn by -2
-4x + 6y = -36
4x + y = 8
/*add the eqtns
-4x + 6y + 4x + y = -36 + 8
7y = -28
y = -4
Plug in the y value into either of the first two eqtns:
2x - 3*(-4) = 18
2x +12 = 18
2x = 18 - 12
2x = 6
x = 3
(x,y)=(3,-4)
4x + y = 8
/*multiply first eqtn by -2
-4x + 6y = -36
4x + y = 8
/*add the eqtns
-4x + 6y + 4x + y = -36 + 8
7y = -28
y = -4
Plug in the y value into either of the first two eqtns:
2x - 3*(-4) = 18
2x +12 = 18
2x = 18 - 12
2x = 6
x = 3
(x,y)=(3,-4)