Question

What's the length of side AB in ΔABC shown?

A. √15
B. 6
C. 5
D. √313



PLEASE DON'T PUT WRONG ANSWER!

Answer 1

The pythagroean theorem says a² + b² = c² and we're given a and c in this case

12² + b² = 13²

144 + b² = 169; subtract 144 from both sides

b² = 25; square root both sides

b = 5 so the length of side AB is C) 5

Answer 2

THE CORRECT CHOICE IS C

Now in this problem we aren't finding for the hypotenuse, we're actually finding for one side.

The hypotenuse is 13 and the other side is 12.

Using Pythagoras' theorem

side² = hyp²–side²

AB² = 13² – 12²

AB² = 169 – 144

AB² = 25

AB = √25

AB = 5

THEREFORE IT'S C