Respuesta :

Answer:

see below

Step-by-step explanation:

CM is the bisector of ∠AMB

bisector means divide into two equal parts.

so x + 20 = 3x - 40

solve for x:

  • x + 20 = 3x - 40  (combine similar terms)
  • 20 + 40 = 3x - x   (simplify)
  • 60 = 2x                (divide 2 both sides)
  • x = 60/2
  • x = 30

now substitute x=30 back into the equation

  • x + 20 = 3x - 40
  • 30 + 20 = 3(30) - 40
  • 50 = 90 - 40
  • 50 = 50  ------>> both are equal