Answer:
B
Step-by-step explanation:
The line from the vertex to the base is a perpendicular bisector and divides the isosceles triangle into 2 right triangles with hypotenuse x
Using Pythagoras' identity in either of the 2 right triangles, then
x² = 12² + 5² = 144 + 25 = 169 ( take the square root of both sides )
x = [tex]\sqrt{169}[/tex] = 13 → B
