How do you solve ３xーy＝８ x=5-2y?

Question

767 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2018-06-04T23:36:00

We already know what x equals so we can just use substitution to find what y is equal to; we can then find the value of x using that.

#y=-1#

#x=7#

Substitue the equation #x=5-2y# into the x vairiable of #3x-y=8#

#3(5-2y)-y=8#

#15-6y-y=8#

#15-7y=8#

#7y=-7#

#y=-1#

We can now substitute the value of y into our original equation

#x=5-2(-1)#

#x=5-(-2)#

#x=7#

So #x=7# and #y=-1#