Question

The three angles in the tiangle are 5x ,6x and 7x work out the size of the largest angle in the triangle

Answer 1

Given :

Angle of triangle are

• 5x
• 6x
• 7x

To find : Size of largest angle (7x)

Steps to follow :

Sum of all angles of triangle = 180°

• Therefore we will add given angle
• Then equate it to 180°
• Find value of x

Solution :

Sum of angle of triangle = 5x + 6x + 7x

Sum of angle of triangle = 18x

180° = 18x

$\sf \implies \: x = \dfrac{180 ^{\circ}}{18} \\ \\\sf \implies \: x = 10 ^{\circ}$

Largest angle = 7x

Largest angle = 7(10°)

Largest angle = 70°

Additional :

Other angle

• Smallest angle = 5x = 5(10°) = 50°
• 6x = 6(10°) = 60°

ANSWER : Largest angle = 70°