Answer:
14d + 12c -4
Step-by-step explanation:
 
        
             
        
        
        
Answer:
Step-by-step explanation:
1:9:3
brian gets x
alex gets 9x
colin gets 3x
Brian and colin receive 40
x + 3x = 40
x = 10
alex gets 9x = £90
 
        
             
        
        
        
Answer:
74º
Step-by-step explanation:
- Ray TV bisects ∠RTS, so ∠RTV=∠STV=(16x-6)º
- We also know that ∠RTS=(26x+18)º
- So, (16x-6)º+(16x-6)º=(26x+18)º
- We don't need parenthesis, 16x-6+16x-6=26x+18
- Combine like terms, 32x-12=26x+18
- Add, 32x=26x+30
- Subtract, 6x=30
- Divide, x=5
- ∠RTV now is [16(5)-6]º=(80-6)º=74º
 
        
             
        
        
        
If you have a calculator, you can use the inverse cos " cos⁻¹ " key. Many upper level books write that as Arccos so as not to confuse you with a negative exponent. We do that because if you take the cosine of any angle, and then the inverse cosine of any angle, it leads you back to the original angle. Think of it as a big "UNDO" button.
To one decimal place, that result is 61.6 degrees.