Respuesta :

Answer:

x=4, y=-4/3. (4, -4/3).

Step-by-step explanation:

8x+9y=20

x=-3y

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8(-3y)+9y=20

-24y+9y=20

-15y=20

y=20/-15

simplify

y=-4/3

x=-3(-4/3)=12/3=4

Answer:

Y=4/-3 X=4

Step-by-step explanation:

We must use substitution. If x is -3y, then we can either substitute all the x’s or y’s. I’ll substitute y.

8x+9y=20

8x+-3x=20

5x=20

x=4

x=-3y, so -3y=4. Y=4/-3