Respuesta :

7x+9y=-41

x+3y=1 so x = 1 -3y

replace x = 1 -3y into 7x+9y=-41

7x+9y=-41

7(1-3y) + 9y = - 41

7 - 21y + 9y = -41

-12y = - 48

y = 4

x+3y=1

x + 3 (4) = 1

x + 12 = 1

x  = -11


answer x = -11 and y = 4


dexteright02
7x + 9y = -41 (I)
x + 3y = 1 (II)
---------------------
7x + 9y = -41 
x + 3y = 1 *(-7)
---------------------
7x + 9y = -41 
-7x -21y = -7
---------------------
-12y = - 48 .(-1)
12y = 48
y = 48/12
y = 4

Substitute "y" in equation (II), we have:

x + 3y = 1
x + 3.(4) = 1
x + 12 = 1
x = 1 - 12
x = -11

Answer: 
[tex]\boxed{(x,y) = (-11, 4)}[/tex]

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