No they are not, 6/8 could also be represented as 3/4. Therefore they are not equivalent. You would divide each side by the factor they have in common such as 2.
how many pounds does he feed his dogs for each meal?
-2x-y=3 ...(1)
x+2y=4 ...(2)
multiply (2) by 2 and add to (1)
-2x-y+2x+4y=3+8
3y=11
y=11/3
from (2)
x=4-2y=4-2(11/3)
or x=4-(22/3)
=(12-22)/3=-10/3
An equvilent equation
remember you can do anything to an equation as long asyou do it to both sides
assuming yo have
x+y=1 and
x-3y=9
mulitply both by 2
2x+2y=2
2x-6y=18
those are equvilent
ok, solve initial
x+y=1
x-3y=9
multiply first equation by -1 and add to 2nd equation
-x-y=-1
<u>x-3y=9 +</u>
0x-4y=8
-4y=8
divide both sides by -4
y=-2
sub back
x+y=1
x-2=1
add 2
x=3
x=3
y=-2
(3,-2)
if we test it in other one
2x+2y=2
2(3)+2(-2)=2
6-4=2
2=2
yep
2x-6y=18
2(3)-6(-2)=18
6+12=18
18=18
yep
solution is (3,-2)
