Question

The measures of all the angles in the given figure is

• A. ${85}^0,{50}^0,{135}^0,{130}^0$
• B. ${80}^0,{55}^0,{130}^0,{135}^0$
• C. ${75}^0,{60}^0,{125}^0,{40}^0$
• D. ${95}^0,{45}^0,{115}^0,{40}^0$

Answer 1

The correct option is A

${85}^0,{50}^0,{135}^0,{130}^0$

Inner angle at C is $={180}^0-{95}^0={85}^0$ [Linear pair]

Inner angle at A = ${180}^0-({85}^0+{45}^0)={180}^0-{130}^0$ [Sum of all the angles of a triangle is ${180}^0$]

$={50}^0$

Outer angle at B is $={180}^0-{45}^0={135}^0$ [Linear pair]

Outer angle at A is $={360}^0-({135}^0+{95}^0)={360}^0-{230}^0$ [Sum of all the exterior angles of triangle is ${360}^0$]

$={130}^0$