Find x in the following figures.

Explanation

(a) Sum of the measures of the external angles,

`125^@+125^@+x=360^@`
`250^@+x=360^@`

`x=110^@`
`y=90^@`
Sum of the measures of the external anglesis360^@
`60^@+90^@+70^@+x+y=360^@`
`60^@+90^@+70^@+x+90^@=360^@`
`310^@+x=360^@`
`x=50^@`