SOLUTION: Solve for y. {{{ x^2/16 + y^2/4 = 1 }}}. I'm kind of lost because I square rooted the whole thing but thats wrong, so I'm confused.

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: Solve for y. {{{ x^2/16 + y^2/4 = 1 }}}. I'm kind of lost because I square rooted the whole thing but thats wrong, so I'm confused.      Log On


   

Question 1035048: Solve for y. +x%5E2%2F16+%2B+y%5E2%2F4+=+1+. I'm kind of lost because I square rooted the whole thing but thats wrong, so I'm confused.
Found 2 solutions by Alan3354, Edwin McCravy:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Solve for y. +x%5E2%2F16+%2B+y%5E2%2F4+=+1+
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Multiply by 4
+x%5E2%2F4+%2B+y%5E2+=+4+
+y%5E2+=+4+-+x%5E2%2F4
+y+=+sqrt%284+-+x%5E2%2F4%29

Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
+x%5E2%2F16+%2B+y%5E2%2F4+=+1+

Multiply through by LCD = 16

x%5E2%2B4y%5E2+=+16

Addd -x2 to both sides:

4y%5E2+=+16-x%5E2

Divide both sides by 4

y%5E2+=+%2816-x%5E2%29%2F4

Use the principle of square roots:

y+=+%22%22+%2B-+sqrt%2816-x%5E2%29%2F2

Edwin