Bài giải:

Ta có: $\widehat{ADC}=2\widehat{.CBD}=2.\widehat{ADB}={{2.59}^{0}}={{118}^{0}}$

Xét tứ giác ABCD ta có:

$2.\widehat{ADC}+2.\widehat{BAD}={{360}^{0}}$             (vì $\widehat{BAD}=\widehat{BCD};\widehat{ADC}=\widehat{ABC}$ )

Thay số: ${{2.118}^{0}}+2.\widehat{BAD}={{360}^{0}}$

Suy ra: $\widehat{BAD}={{62}^{0}}$

Do đó: $\widehat{DAC}=\widehat{BAC}=\frac{\widehat{BAD}}{2}=\frac{{{62}^{0}}}{2}={{31}^{0}}$

Vậy x = 31⁰