A)x=45
B)x=90
C)x=20
D)x=4.5

Answer:
x=4.5
Step-by-step explanation:
We know that if all sides are congruent then all angles must also be congruent, therefore you can solve for x with the following equation:
[tex]20x=90[/tex]
Solve
[tex]x=4.5[/tex]