Question 1119114
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<pre>
For ANY right angled triangle with the legs "a" and "b" and the hypotenuse "c", 


    where c = {{{sqrt(a^2+b^2)}}},

    
the radius of the inscribed circle  r = {{{(a + b - c)/2}}}.


So, in your case the radius of the inscribed circle is  {{{(3 + 4 - 5)/2}}} = 1 unit.
</pre>

See the lesson

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/word/geometry/Solved-problems-on-tangent-lines-released-from-a-point-outside-a-circle.lesson>Solved problems on tangent lines released from a point outside a circle</A>

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