SOLUTION: The directions for this say to solve the equation by "suitable methods"....I am confused. Please help. y-1=[(y+1)/4]^1/2

Algebra ->  Radicals -> SOLUTION: The directions for this say to solve the equation by "suitable methods"....I am confused. Please help. y-1=[(y+1)/4]^1/2      Log On


   



Question 1921: The directions for this say to solve the equation by "suitable methods"....I am confused. Please help.
y-1=[(y+1)/4]^1/2

Answer by longjonsilver(2297) About Me  (Show Source):
You can put this solution on YOUR website!
first, square both sides... %28y-1%29%5E2 = (y+1)/4 then move the 4 to the other side and multiply out the bracket...
4y%5E2+-+8y+%2B+4+=+y+%2B+1
now get everything on one side... 4y%5E2+-+9y+%2B3+=+0
Solve this now, ie find the y value(s) where all this does equal zero.
Best way is factorising, but i don't think this factorises well, so that leaves the quadratic formula as the best solution.
y+=+%28-b+%2B-+sqrt%28b%5E2+-+4ac%29%29%2F%282a%29
y+=+%289+%2B-+sqrt%2881+-+4%2A4%2A3%29%29%2F%288%29
y+=+%289+%2B-+sqrt%2833%29%29%2F8%29
so y+=+%289%2Bsqrt%2833%29%29%2F8%29 or y+=+%289-sqrt%2833%29%29%2F8%29

jon.