Answer:
4
Step-by-step explanation:
since the triangle is isosceles, the vertical line splits the base into two equal halves. the triangle is now 3 - x - 5.
use Pythagorean theorem [tex]a^{2} +b^{2} =c^{2}[/tex], where c is the hypotenuse and a and b are the other side lengths
[tex]5^{2} =3^{2} +x^{2}[/tex]
25=9+[tex]x^{2}[/tex]
[tex]x^{2}[/tex] = 16
x = [tex]\sqrt{16}[/tex]
x = ±4
since a measure of distance cannot be negative, x = 4, not -4.
