Question 625376
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This is given:
{{{x^2+y^2=64}}}
Let's rearrange to get: {{{y^2=64-x^2}}}
{{{y=sqrt(64-x^2)}}}
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Remember that negative numbers do not have a square root. So, for {{{sqrt(64-x^2)}}} to be existent {{{64-x^2}}} must be greater than or equal to zero:
{{{64-x^2 > 0}}}
{{{x^2<64}}}
{{{x>-8}}} and {{{x<8}}}
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So the domain of x is [-8,8]

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