How do you solve 8y-1=x, 3x=2y?

2 Answers
Nov 26, 2016

I found: x=1/11 and y=3/22

Explanation:

We can trysubstituting the first equation, for x, intothe second to get:
3*(color(red)(8y-1))=2y
Solve for y:
24y-3=2y
22y=3
So: y=3/22
Using this value back into the first equation:
8*(3/22)-1=x
x=(24-22)/22=2/22=1/11

(x,y)=(1/11,3/22)

Explanation:

We have two equations:

8y-1=x
3x=2y

We can substitute in the value of x (in terms of y) from the first equation into the second, and then solve for y. Like this:

3(8y-1)=2y

24y-3=2y

22y=3

y=3/22

And then we substitute into either of the initial equations (I'll do both to show we'll get the same answer for x):

8y-1=x

8(3/22)-1(1)=x

24/22-1(22/22)=x

24/22-22/22=2/22=1/11=x

or:

3x=2y

3x=2(3/22)

3x=3/11

x=1/11