Question

The sum of the angles of a triangle 180 * . if the three angles are (2x+15)* , 85* and (x+20)* , the value of x is.

* This is a degree​

Answer 1

AnswEr :

• The value of x is 20 .

GivEn :

• 1st angle = 180°

• 2nd angle = ( 2x + 15 )°

• 3rd angle = ( x + 20 )°

To find :

• Value of x = ?

━━━━━━━━━━━━━━

Formula usEd :

To solve the above question you need to know the basic concept of the 'Angle Sum Property of a Triangle '.

✩ Angle sum property of triangle means that the sum of all the 3 interior angles of a triangle is 180° .

In any ΔABC,

$\large\dag \: { \boxed{ \sf{\red{\angle A + \angle B + \angle C = {180}^{ \circ}}}}}$

Proceeding towards the question...!

━━━━━━━━━━━━━━

SoluTion :

By Angle Sum Property of a Triangle ,

$: \implies \sf \: \: \: (2x + 15) + 85 + (x + 20) = 180$

$: \implies \sf \: \: \: 3x + 120 = 180$

$: \implies \sf \: \: \: 3x = 180 - 120$

$: \implies \sf \: \: \: 3x = 60$

$: \implies \sf \: \: \: x = \dfrac{60}{3}$

$: \implies \sf \: \: \: { \underline{ \boxed{ \sf{ \purple{x = {20}^{ \circ}}}}}} \: \bigstar$

Therefore, value of x is 20°.

━━━━━━━━━━━━━━

Answer 2

Step-by-step explanation:

AnswEr :

The value of x is 20 .

GivEn :

1st angle = 180°

2nd angle = ( 2x + 15 )°

3rd angle = ( x + 20 )°

To find

Value of x = ?

━━━━━━━━━━━━━━

Formula usEd :

To solve the above question you need to know the basic concept of the 'Angle Sum Property of a Triangle '.

✩ Angle sum property of triangle means that the sum of all the 3 interior angles of a triangle is 180° .

In any ΔABC,

∠A+∠B+∠C=180

∘

Proceeding towards the question...!

━━━━━━━━━━━━━━

SoluTion

By Angle Sum Property of a Triangle ,

(2x + 15) + 85 + (x + 20) = 180

3x + 120 = 180

3x = 180 - 120

⟹3x=60

:⟹

x=20

∘

★

Therefore, value of x is 20°.