1. I have also another algebric quesion to ask. I found this equation EXTREMELY EASY, but many of my friends in the class don't know the ans. not even the smartest math guy in the class, he has a deformed head, he says that he studies too much and it goes weird. so heres the quesrtion.

if x+z=y,
and x+9(7-7)=y,
what is z+x+y?
I ansered x+y.
(oh yeah, this has nothing to do with the previous question.)
is this question really that difficult? and did i get the answer correct?? w the?

2. Yes, x+y+z = x+y. ----one correct answer.

Also,
x+y+z = 2x ----another correct answer.
x+y+z = 2y ----still another correct answer.

Is the question really that difficult?
No.
In fact, it is really that easy.

3. Originally Posted by ticbol
Yes, x+y+z = x+y. ----one correct answer.

Also,
x+y+z = 2x ----another correct answer.
x+y+z = 2y ----still another correct answer.

Is the question really that difficult?
No.
In fact, it is really that easy.
how did you get 2x abd 2y as answers?

4. You figured correctly that z=0. That is why you got x+y+z = x+y.

So if z=0,
x+z=y,
x+0 = y
x = y ------***

Then,
x+y+z
= x +y +0
= x +y -----(1)

But x=y,
So, substitute that into (1),
= y +y
= 2y

Also, since x=y, then y=x.
So, substitute that into (1),
= x +x
= 2x

-------------------------
But why is z equal to zero?
Did you guess that, or you found it?

Anyway, this is why z=0.

if x+z=y,
and x+9(7-7)=y,
what is z+x+y?

x +9(7-7) = y
x +9(0) = y
x +0 = y
x = y -----***
Substitute that into "if x+z=y",
x +z = y
y +z = y
z = y -y
z = 0

That is why.