Question

2y-9=y-5

Answer 1

2y - 9 = y - 5

Add 9 to both sides:

2y = y + 4

Subtract y to both sides:

y = 4

Answer 2

@Captainpoptart didn't you get it ?yet....

Answer 3

2y - 9 = y - 5
y=4
because you add both sides, then you subtract the y to both sides
if you have anymore trouble, use this
http://www.wolframalpha.com/