Inradius of a right triangle, r = (a + b - c)/2

This type of question, asked 3 times: 25 Jul 2023 S4, 17 Sep 2025 S1, 19 Sep 2025 S1. All 3 questions below, oldest first.

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Question 1
25 Jul 2023 S4
73 $A circle of radius 4 cm is drawn inscribed in a right angle triangle ABC, right angled at C. If AC = 12 cm, then the value of CB is:$
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Question 2
17 Sep 2025 S1
74 $A circle is inscribed within a right triangle. Considering that the lengths of the two legs measure 6 cm and 8 cm,what is the radius of the inscribed circle?$
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Question 3
19 Sep 2025 S1
74 $A circle is inscribed in a right triangle with legs of length 5 and 12. What is the radius of the circle?$
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Question 1