Try this option ↓
Step-by-step explanation:
1) according to the condition two angles are equal, then two sides are equal also, it means
2) √x+4=√(5x+4);
3) the 'x' can be calculated if to solve this equation:
[tex]\sqrt{x} +4=\sqrt{5x+4}[/tex];
[tex]x+16+8\sqrt{x} =5x+4;[/tex]
[tex]4x-12=8\sqrt{x} ;\ => \ x-2\sqrt{x} -3=0;[/tex]
[tex]\left \{ {{\sqrt{x} =-1} \atop {\sqrt{x} =3}} \right. \ => \ x=9.[/tex]
4) finally, answer: 9.
