Now find Y
Hello, nquadr!
I'd get rid of that book . . . it's juvenile.
And, I'm afraid, so are you . . .
The book had the following answer for C.
. .
What a stupid way to publish an answer!
Did you simplify it?
It's obvious that it never occured to them !
I'll start over . . .
We have: .
Add the equations: .
. .
Substitute into [2]: . . and they stopped here?!
Simplify: .
. . Therefore: .