The angles of a triangle are (x − 40)°, (x − 20)° and (1/2 −

1.	The angles of a triangle are (x − 40)°, (x − 20)° and (1/2 − 10)°. Find the value of x.
Answer» Given the angles of a triangle are (x − 40)°, (x − 20)° and (1/2 − 10)°. We know that sum of all the angles of a triangle = 180° (x − 40)° + (x − 20)° + (1/2 − 10)° = 180° x + x + (x/2) – 40° – 20°– 10° = 180° x + x + (x/2) – 70° = 180° (5x/2) = 180°+ 70° (5x/2) = 250° x = (2/5) × 250° x = 100° Hence the value of x is 100°

The angles of a triangle are (x − 40)°, (x − 20)° and (1/2 − 10)°. Find the value of x.

Answer»

Given the angles of a triangle are (x − 40)°, (x − 20)° and (1/2 − 10)°.

We know that sum of all the angles of a triangle = 180°

(x − 40)° + (x − 20)° + (1/2 − 10)° = 180°

x + x + (x/2) – 40° – 20°– 10° = 180°

x + x + (x/2) – 70° = 180°

(5x/2) = 180°+ 70°

(5x/2) = 250°

x = (2/5) × 250°

x = 100°

Hence the value of x is 100°