What is the value of x+y for the equation? y=4x-5, and y=-4x+19

1 Answer
Apr 28, 2018

Answer:

#x+y=10#

Explanation:

#y=4x-5#
#y=-4x+19#

From this we can say

#4x-5=y=-4x+19#

#4x-5=-4x+19#

Now add #5# to both sides of the equation:

#4x-5 \ ul(+5) =-4x+19 \ ul(+5)#

#4x=-4x+24#

Then add #4x# to both sides of the equation:

#4x \ ul(+4x) =-4x \ ul(+4x) +24#

#8x=24#

Now we can divide both sides of the equation by #8#, or you can say, that

#8x=24#

so

#x=24/8= 3#

Knowing the value of #x#, we can easily find the value of #y#.

#y=4x-5#

#4x-5=4*3-5=12-5=7#

So

#x=3 and y=7#

Therefore

#x+y=3+7=10#