Answer:
[tex]x=23[/tex]
Step-by-step explanation:
The only difference between these two triangles is that they are rotated differently. If we line up their congruent sides we can see that BC is congruent to EF. EF is given to us, but BC is an equation. Since we know they are the same length, we can set them equal and solve for x.
[tex]19=x-4\\x=23[/tex]
Hope this helps!