Question

the measures of two angles of a triangle are 60digree and 40digree measure of the third angle​

Answer 1

Given :

• The two angles of a triangle are 40° and 60° .

$\rule{200pt}{3pt}$

To Find :

• Find the measure of 3rd angle.

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Solution :

$\color{maroon}{✪}$Concept Used :

• Angle sum Property :

${\underline{\boxed{\color{orange}{\textsf{ Sum of all the angles of a triangle = 180° }}}}}$

$\qquad{━━━━━━━━━━━━━━━━━━━━━}$

$\color{maroon}{✪}$Calculating the 3rd angle :

${\longmapsto{\qquad{\sf{ ∠1 + ∠2 + ∠3 = 180° }}}} \\ \\ \ {\longmapsto{\qquad{\sf{ 60° + 40° + ∠3 = 180° }}}} \\ \\ \ {\longmapsto{\qquad{\sf{ 100° + ∠3 = 180° }}}} \\ \\ \ {\longmapsto{\qquad{\sf{ ∠3 = 180° - 100° }}}} \\ \\ \ {\qquad{\textsf{ 3rd angle of Triangle = {\red{\sf{ 80° }}}}}}$.

$\qquad{━━━━━━━━━━━━━━━━━━━━━}$

$\color{maroon}{✪}$Therefore :

❝ Third angle of the Triangle is 80° .❞

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Answer 2

$\small\bold\red{Given:- }$

• First angle is 60°
• Second angle is 40°

$\small\bold\green{To Find :-}$

• The third angle ?

$\small\bold\pink{Let \: us \: assume:-}$

• Third angle be x°

$\small\bold\blue{Solution:-}$

$\small \bold \purple{we \: know \: \: sum \:of \: all \: angles \: in \: triangle\: is \: 180 \degree \: }$

According to the question :-

$\angle1 + \angle2 + \angle3 = 180 \degree$

$60 \degree + 40 \degree + x = 180 \degree$

100° + x = 180°

x = 180° - 100°

x = 80°

Hence,

• The third angle = x =80°