Solve the system of equations by any method: substitution, or elimination? y=2x-4y and 4x+1=10y+7

Question

substitution

1745 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2018-03-31T01:06:45

No solution - the two lines are parallel

Let's use substitution:

Equation 1:

$y=2x-4y$

$5y=2x=>10y=4x$

We can substitute that into equation 2:

$4x+1=10y+7$

$10y+1=10y+7$

And we run into a problem with the question - these equations have no joint solution.

We can graph the two of them to see:

Equation 1:

$10y=4x=>y=2/5x$

Equation 2:

$10y=4x-6=>y=2/5x-3/5$

These two equations describe 2 parallel lines:

graph{(y-2/5x)(y-2/5x+3/5)=0}