Answer:
x = 13
Step-by-step explanation:
Since AD is a straight line, then the 3 angles at C sum to 180° , thus
∠ BCE = 180° - (90 + 64)° = 180° - 154° = 26°
The external angle of a triangle is equal to the sum of the 2 opposite interior angles.
∠ ABE is an exterior angle of the triangle, thus
3x = x + 26 ( subtract x from both sides )
2x = 26 ( divide both sides by 2 )
x = 13
