Respuesta :

12^2+x^2=15^2
144+x^2=225
- 144 -144
=81= 9
X=9

Answer:

x=9

Step-by-step explanation:

Use Pythagorean Theorem -> a^2 + b^2 = c^2

a^2 + b^2 = c^2

(12^2) + b^2 = (15^2)

144 + b^2 = 225

225 - 144 = 81

√81 = 9

x = 9