Saved Bookmarks
| 1. |
In the given, figure , O is the centre of the circle and AD is a tangent to the circle at.A if `angle CAD =55^@` and `angle ADC=25^@`, then find `angle ABO`. |
|
Answer» (i) Join OA and OC. (ii) `angle ACD =180^@-80^@=100^@`. (iii) `angle ACB and angle ACD ` are supplementary. `rArr angle ACB +angle ACD =180^@`. `rArr angle ACB =80^@` (iv) `angle AOB =2angle ACB.rArr AOB =2xx80^@=160^@` (v) Now, In `Delta AOB`, `angle O+angle A+angle B=180^@` `160^@+x+x=180^@` `2x=20^@` `x=10^@` `therefore` Hence, option (a) is the correct answer. |
|