Given :
The given two triangles are similar .
To find :-
The value of x .
Solution :
In larger triangle :-
90 + y + y = 180
2y = 180 - 90
2y = 90
y = 45°
As we know that ,
Corresponding Angles of similar triangles are same ,
15x = 45
x = 45/15
x = 3