Question

three outer angles of quadrilateral are 80⁰,100⁰,120⁰ find the remaining outer angles and the measures of their inner angles​

Answer 1

Given:-

Outer angles of quadrilateral ie., $80^{0},100^{0}&120^{0}$

To Find:-

Inner angles and remaining outer angle.

Explanation:-

Consider a quadrilateral ABCD

Outer angles which are given are shown in red colour.

Angle subtended by a straight line is $180^{0}$

$\text{Therefore},\\ \text{inner angle A}=180-120=60^{0}\\\\\text{Similarly,} \text{inner angle B}=180-80=100^{0}\\\\\text{inner angle D}=180-100=80^{0}\\\\\text{inner angle C}=360-(60+100+80)=120^{0}\\\\\text{outer angle at C}=180-120=60^{0}$