What’s the length of side AB in ABC shown?
A. 6
B. 5
C. Square root 15
D. Square root 313

The length of side AB in ΔABC is 5 (B)
Step-by-step explanation:
Use Phytagoras Theorem :
AB² = BC² - AC²
AB² = 13² - 12²
AB² = 169 - 144
AB² = 25
AB = √25
AB = 5
So, the length of side AB in ΔABC is 5 (B)
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