Question 354699
Hi,
If I am understanding your question properly
.
{{{r^2 - 10r + 25 - x^2 = 0}}}
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{{{r^2 - 10r + 25 = x^2 }}}
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{{{sqrt(r^2 - 10r + 25)= sqrt( x^2) }}}
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{{{sqrt((r - 5)^2) = x }}}
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{{{(r - 5) = x }}}