Respuesta :

Answer:

∠A=65º

Step-by-step explanation:

  • A angle of a line is 180º, so we can say that angle ABC=(180-6x)º
  • The interior angkes of a triangle is 180º, so (x+40)º+(3x+10)º+(180-6x)º=180º
  • Remove parenthesis, x+40+3x+10+180-6x=180
  • Combine like terms, -2x+230=180
  • Subtract 180, -2x=-50
  • Divide by -2, so x=25

Now:

  • ∠CAB=(25+40)º=65º
  • ∠ABC=[180-6(25)]º=30º
  • ∠BCA=[3(25)+10]=85º