Answer:
x = 15°
Step-by-step explanation:
Here Δ EFD ≅ Δ EBC
therefore ∠ EDF = ∠ ECB
∵ ∠ EDF = 3 x
∴ ∠ ECB = 3 x
As we know that the sum of all angles of a triangle is 180° .
∠DAC + ∠ DCA + ∠ ADC = 180°
x + 3 x + 8 x = 180°
12 x =180°
x = 180°/12
x = 15°
