SOLUTION: How do you solve √(4y+5)-√(y-1)=3

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Question 342226: How do you solve √(4y+5)-√(y-1)=3
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
sqrt%284y%2B5%29-sqrt%28y-1%29=3
sqrt%284y%2B5%29=sqrt%28y-1%29%2B3
Square both sides,
4y%2B5=%28y-1%29%2B6sqrt%28y-1%29%2B9
4y%2B5=y%2B8%2B6sqrt%28y-1%29
3y-3=6sqrt%28y-1%29
3%28y-1%29=6sqrt%28y-1%29
%28y-1%29=2sqrt%28y-1%29
Use a substitution, let u=y-1
u=2%2Asqrt%28u%29
Square both sides,
u%5E2=4u
u%5E2-4u=0
u%28u-4%29=0
Two solutions:
u=0
y-1=0
highlight%28y=1%29
.
.
.
u-4=0
y-1-4=0
y-5=0
highlight%28y=5%29