Question 81194
8x-4y=16        ----(1)
y = 2x - 4      ----(2)

From the second equation 
we have
y =2x - 4   ----- (3)

substituting this value in (1) equation, we get

8x - 3(2x - 4) = 16
8x - 6x + 12 = 16
2x  + 12 = 16
2x + 12 - 12 = 16 - 12    (subtractinc 12 from both sides)
2x = 4
2x/2   =  4/2        (dividing both sides by 2)
x = 2

Putting this value of x  in (3) equation we get

y = 2(2) - 4
y = 4 - 4
y = 0

so solution is x = 2  and y = 0

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