How do you solve the system #x+3y=-4# and #2x+6y=5# using substitution?

1 Answer
Daniel L.
Oct 16, 2016

This systen has no solutions. See explanation for details.

Explanation:

The original system is:

#{(x+3y=-4),(2x+6y=5):}#

To solve it using substitution we have to calculate one of the variables from one equation to substitute it in the other. We can easily calculate #x# from the first equation:

#x=-4-3y#

Now we put the value to the second equation:

#2(-4-3y)+6y=5#

If we try to calculate #y# from this equation we get:

#-8-6y+6y=5#

If we reduce like terms we get:

#-8=5#

This equality is of course false which means that the original system has no solutions.

Related questions
See all questions in Systems Using Substitution
Impact of this question
5580 views around the world
You can reuse this answer
Creative Commons License