How do you solve #2x = 4# and #2x – y = 5#?

1 Answer
Aug 21, 2015

Answer:

#{(x = 2), (y = -1) :}#

Explanation:

Notice that you can find the value of #x# from the first equation by dividing both sides by #2#

#(color(red)(cancel(color(black)(2))) * x)/color(red)(cancel(color(black)(2))) = 4/2#

#x = color(green)(2)#

Now simply take this value of #x# and plug it into the second equation. This will allow you to find the value of #y#

#2x - y = 5#

#2 * (2) - y = 5#

#4 - y = 5#

This is equivalent to

#y = 4 -5 = color(green)(-1)#