Here's the question you clicked on:
henaoalexandra
8x-4y=20
what are you solving for?
x=15/6 solve for one variable and plug it back into the original equation to get the other.. so 8x-4y=20 4y=8x-20 y=(8x-20)/4----y=2x-5 plug y value back into original equation?? this may not be right!!!
8x-4y=20 first divide everything by 4 and you get: 8x/4-4y/4=20/4 2x-y=5 add y 2x-y+y=5+y 2x=5+y divide by 2 to isolate x 2x/2=(5+y)/2 x=(5+y)/2 so far you solved for x Now if you want to solve for y here is what you do: 8x-4y=20 first divide everything by 4 and you get: 8x/4-4y/4=20/4 2x-y=5 subtract 2x 2x-2x-y=5-2x -y=5-2x divide by (-1) both sides of the equation (-1)(-y)=(-1)(5-2x) y=-5+2x or y=2x-5 This is as far as you can go with these kind of equation, unless you are given more info.
dwelsher suggests to plug back into the original equation, but that would give you 0=0... and you did not find x nor y.