SOLUTION: We have tried this problem and can't get it - My mom can't figure it out either. Please help y-1 a-b ____ = ______ y+1 a+b solve for y It

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Question 24207: We have tried this problem and can't get it - My mom can't figure it out either.
Please help
y-1 a-b
____ = ______
y+1 a+b solve for y
It tells me to cross multiply and I have gotten to this step
(y-1)(a+b)=(y+1)(a-b)
Do I now go to ya-1b = ya-1b - this is where I am lost please help
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Your real problem is that you haven't quite figured out the multiplication when
you have terms to add in the factors. You just need practice and new ways to
look at it.
How about this:
(3 + 4)(6 + 2)
multiply the 6 times the numbers in the first parenthesis. so far we have:
18 + 24
now multiply the 2 times the numbers in the first parenthesis. we have:
6 + 8
now add them
18 + 24 + 6 + 8 = 56
now check
(3 + 4)(6 + 2) = 7 * 8 = 56
practice it this way instead of with symbols
now the problem:
%28y+-+1%29+%2F+%28y+%2B+1%29+=+%28a+-+b%29+%2F+%28a+%2B+b%29
cross multiply:
%28y+-+1%29+%2A+%28a+%2B+b%29+=+%28y+%2B+1%29+%2A+%28a+-+b%29
now follow the same process you did with (3 + 4)(6 + 2)
%28y+%2A+a%29+-+a+%2B+%28y+%2A+b%29+-+b+=+%28y+%2A+a%29+%2B+a+-+%28y+%2A+b%29+-+b
subtract y*a from both sides
+-a+%2B+%28y+%2A+b%29+-+b+=+%2Ba+-%28y+%2A+b%29+-b
add b to both sides
+-a+%2B+%28y+%2A+b%29+=+a+-%28y+%2A+b%29
now you want to add y*b to both sides
-a+%2B+2+%2A+y+%2A+b+=+a
add a to both sides
2+%2A+y+%2A+b+=+2+%2A+a
divide both sides by 2*b
y+=+a+%2F+b
unless I goofed, that's the answer
try things like (2 + 5 - 1)(4 - 2 + 7) and you'll be a real expert!