SOLUTION: Solve each of the following systems by substitution 8x -4y = 16 y = 2x-4

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Question 75601: Solve each of the following systems by substitution
8x -4y = 16
y = 2x-4
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Plug the 2nd equation into y of the 1st equation
8x+-4%282x-4%29+=+16
8x+-8x%2B16+=+16
16=16
Since this is true for all x, there are an infinite number of solutions. If you solve the 1st equation for y you get:
8x+-4y+=+16
-4y=16-8x
y=-4%2B2x
y=2x-4
Which is the same as the 2nd equation. Since they are the same, they intersect at an infinite number of points.