Answer: (choice B) 12
Explanation:
In an isosceles triangle, two sides are equal in length. From the information given, the triangle has sides with lengths \(10\), \(13\), and \(13\), with a base of \(x\). Since it's isosceles, the two equal sides are \(13\) each, and the base is \(10\).
To find the value of \(x\), you can use the Pythagorean theorem. Let \(x\) be the height of the triangle, and then we have:
\[ x^2 + \left(\frac{10}{2}\right)^2 = 13^2 \]
\[ x^2 + 25 = 169 \]
\[ x^2 = 144 \]
\[ x = 12 \]
So, the correct answer is \(x = 12\), which matches Choice B.