Answer:
pythagoras theorem
[tex]a^2+b^2=c^2[/tex]
so we have a and b
12 and 9
so ... [tex]12^2+9^2 = 225[/tex]
take the square root to find c, since 225 is c^2
so √225 = c = 15
B) 15
Step-by-step explanation:
This is a right triangle and in right triangles the square length of hypotenuse is equal to the sum of square length of base and side length
9^2 + 12^2 =√hypotenuse
225 = √hypotenuse
15 = hypotenuse
