Respuesta :
Answer:
(x, y ) = (- 2, 3 )
Step-by-step explanation:
given the 2 equations
7x - 2y = - 20 → (1)
9x + 4y = - 6 → (2)
multiply (1) by 2 making the coefficients of y equal and opposite
14x - 4y = - 40 → (3)
add (2) and (3) term by term
(9x + 14x ) + (4y - 4y ) = (- 6 - 40 )
23x = - 46 ( divide both sides by 23 )
x = - 2
substitute x = - 2 into either (1) or (2) for y
(2) - 18 + 4y = - 6 ( add 18 to both sides )
4y = 12 ( divide both sides by 4 )
y = 3
solution is (- 2, 3 )