SOLUTION: sqrt (y) + sqrt (y+7) = 7 please help me solve for the unknown and show all work

Question 93423This question is from textbook
: sqrt (y) + sqrt (y+7) = 7 please help me solve for the unknown and show all work This question is from textbook

Answer by ankor@dixie-net.com(22740) (Show Source): You can put this solution on YOUR website!
sqrt (y) + sqrt (y+7) = 7
:
Subtract sqrt(y) from both sides:
sqrt(y+7) = 7 - sqrt(y)
:
Square both sides, FOIL (7-sqrt(y))*(7-sqrt(y)), gets rid of radical on the left
y + 7 = 49 - 7*sqrt(y) - 7*sqrt(y) + y
y + 7 = 49 - 14*sqrt(y) + y
:
Arrange everything on the left except the radical remains on the right:
y - y + 7 - 49 = 14*sqrt(y)
-42 = 14*sqrt(y)
:
Square both sides, gets rid of the radical on the right, (square 14 also)
+1764 = 196y
:
y = 1764/196
:
y = 9
:
:
Check solution in original equation:
sqrt (y) + sqrt (y+7) = 7
sqrt(9) + sqrt(9+7) = 7
sqrt(9) + sqrt(16) = 7
:
Did this make sense to you?

RELATED QUESTIONS
Solve for the unknown and check:... (answered by Big Poop)

i am having trouble with how to solve for the unknown in this sqrt of y +(sqrt of y+7)= 7 (answered by dabanfield,stanbon)

also please help me solve for the unknown and show work thanks sqrt (x+11) = sqrt (x) (answered by psbhowmick)

please help me solve {{{3 sqrt 7= sqrt... (answered by edjones)

Please help me solve this equation: sqrt ( y )... (answered by rapaljer)

4sqrt (x) = 20 please help me solve for the unknown and show all... (answered by checkley75)

Please help me solve for the unknown: {{{ sqrt ( x + 11 ) = sqrt ( x ) + 1... (answered by Alan3354)

Please help me solve this. Find the equation of the parabola determined by the given... (answered by lwsshak3)

Please help me answer this, Thank you so much! If x=... (answered by josgarithmetic)