Calculate the length of the third side
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Answer:
length of side = 9
Step-by-step explanation:
This is a right angle triangle so we can use Pythagoras theorem. a^2 + b^2 = c^2
a^2 + 12^2 = 15^2
a^2 = (15^2) - (12^2)
a^2 = 225 - 144
a^2 = 81
a = square root of 81
a = 9