Jika X dan Y memenuhi sistem persamaan 5x -3y=20 dan 3x-5y=-4 maka 6x - 4y=

5x - 3y = 20
3x - 5y = -4
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15x - 9y = 60
15x - 25y = -20
------------------------ —
16y = 80
y = 5

5x - 3y = 20
5x - 3(5) = 20
5x - 15 = 20
5x = 35
x = 7

6x - 4y
= 6(7) - 4(5)
= 42 - 20
= 22

eliminasi x
5x - 3y = 20
3x - 5y = -4
=>15x -9y = 60
15x - 25y = -20
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-9y -(-25y) = 60-(-20)
-9y + 25y = 60+20
16y = 80
y = 80/16
y = 5

subsitusikan y = 5
5x -3y = 20
5x - 3.5 = 20
5x - 15 = 20
5x = 20+15
x = 35/5
x= 7

jadi nilai x = 7 dan y= 5
=> 6x-4y
=> 6.7 - 4.5
=> 42 - 20
=> 22

jadi hasil 6x - 4y = 22