Step-by-step explanation:
[tex] \triangle ACB \cong \triangle DCE... (Given)
\\\\
\therefore \angle A = \angle D...(cact)\\\\
\therefore 3x - 10 = 2x + 10\\\\
\therefore 3x -2x = 10 + 10\\\\
\huge \orange {\boxed {\therefore x = 20}} [/tex]
cact = corresponding angles of congruent triangles.
