ANSWER
B. 10
EXPLANATION
We need to find the value of x first.
It was given that the perimeter of triangle XYZ is 24.
This means that:
XY+YZ+XZ=24
we substitute the expression in terms of x to get;

This implies that


Divide both sides by 4 to get;

|WY|=|ZX|=13-3=10
Um answer f I don’t know math I’m really bad at it
well, it's isosceles so use base angles theorem
the top angle is also x
90 + 2x = 180
subtract 90 from both sides
2x = 90
divide both sides by 2
x = 45 degrees