Question

X-2y=8; 8x+6y=42 substitution

Answer 1

X-2y=8; 6x+6y=42

Try to get a variable all by itself.

x-2y=8

Subtract x on both sides.

-2y= 8-x

Subtract 8 on both sides.

-2y-8= -x

Divide by -1, so that x is not negative.

-2/-1= 2 -8/-1=8

2y+8=x

Now plug that in. 

8(2y+8)+6y=42
16y+64+6y=42
22y+64=42
22y=-22
y=-1

Now, plug that in.

x-2(-1)=8
x+2=8
x=6

(6,-1)

Check.
6-2(-1)=8
6+2=8
8=8

8(6)+6(-1)=42
48-6=42
42=42

The solution is (6,-1)

I hope this helps!
~kaikers

Answer 2

The coordinates would be (6,-1) I think