Question

Three angles in a triangle are x,2x+20° and 7x-10°. What is x?

Answer 1

Answer:

x = 17°

Step-by-step explanation:

The sum of the angles of a triangle = 180°

∴  x° + (2x+20)° + (7x-10)° = 180°

   x + 2x +20 + 7x - 10 = 180

add all the x,

  10x + 20 - 10 = 180

  10x + 10 = 180

bring the constant to the right side,

  10x = 180 - 10

  10x = 170

bring the coefficient to the right side,

   x = 170/10

 ∴   x = 17°