Respuesta :

Answer:

20

Step-by-step explanation:

x is the radius of the circle.  The tangent line is perpendicular to the radius line at that point.  Using Pythagorean theorem:

x² + 15² = (x + 5)²

x² + 225 = x² + 10x + 25

225 = 10x + 25

200 = 10x

x = 20

Answer is:

x = 20. hope this helps