what di di do wrong in this???
the question is: x-8y=18
-16x+16y=-8
i did :
first multiplied the first equation with 2
then
2x-16y=36
-16+16y=-8
-----------
-14x=28
x=28/-14
x=-2
now
x-8y=18
(-2)-8y=18
-8y=18+2
-8y=20
y=20/-8
y= 2.5
plz help me what did i do wrong??
I can't see anything besides that y=-2.5 because you divide by a negitive
oo....ok thanks sally
In your solution, you made a small mistake when rewriting the second equation:
-16x + 16y = -8
You mistakenly wrote:
-16 + 16y = -8
The correct equation should be:
-16x + 16y = -8
To correct your steps:
1. Multiply the first equation by 2:
2(x) - 16(y) = 36
This gives you:
2x - 16y = 36
2. Now, rewrite the second equation correctly:
-16x + 16y = -8
3. Add the two equations together:
(2x - 16y) + (-16x + 16y) = 36 + (-8)
This simplifies to:
-14x = 28
4. To isolate x, divide both sides by -14:
(-14x) / -14 = 28 / -14
This simplifies to:
x = -2
5. Now, substitute the value of x into the first equation:
(-2) - 8y = 18
6. Subtract -2 from both sides:
-8y = 18 + 2
This simplifies to:
-8y = 20
7. To isolate y, divide both sides by -8:
(-8y) / -8 = 20 / -8
This simplifies to:
y = -2.5
After making this correction, you will find that the correct solution is x = -2 and y = -2.5, rather than x = -2 and y = 2.5 that you mentioned in your original solution.