Question 310561
{{{sqrt(y)+sqrt(y+7)=7}}}
{{{sqrt(y)=7-sqrt(y+7)}}}
Square both sides.
{{{y=49-14sqrt(y+7)+(y+7)}}}
{{{0=56-14sqrt(y+7)}}}
{{{14sqrt(y+7)=56}}}
{{{sqrt(y+7)=4}}}
{{{y+7=16}}}
{{{highlight_green(y=9)}}}
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Verify the solution.
{{{sqrt(y)+sqrt(y+7)=7}}}
{{{sqrt(9)+sqrt(9+7)=7}}}
{{{3+sqrt(16)=7}}}
{{{3+4=7}}}
{{{7=7}}}
True, then it's a good solution.