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
