We are given
isosceles triangle
and when we draw perpendicular on third sides , it will divide third sides into two equal parts
so,
opposite =38
adjacent =x/2
hypotenuse =43
now, we can use Pythagoras theorem
[tex] 38^2+(\frac{x}{2})^2=43^2 [/tex]
now, we can solve for x
[tex] \left(\frac{x}{2}\right)^2=405 [/tex]
[tex] x=18\sqrt{5} [/tex]............Answer