Answer:
Step-by-step explanation:
<u>The ratio of sides in 30º-60º-90º triangle is:</u>
<u>If a is 5√3, the length of b is:</u>
- b = a√3 = 5√3 *√3 = 5*3 = 15
 
        
             
        
        
        
Answer:
The answer is:
30 minutes.
Step-by-step explanation:
We are given the following information:
at 160 m/min, tool life = 5 min.
at 120 m/min, tool life = 17 min.
This means that as the speed reduced from 160 m/min to 120 m/min, the tool life increased from 5 min. to 17 min, hence the difference between the changes are:
speed = 160 - 120 = 40 m/min
tool life = 17 - 5 = 12 min.
Therefore, it can be concluded that a change of speed of 40 m/min, increases the tool life by 12 min.
40 m/min = 12 min
∴ 1 m/min = 12/40 min.
∴ 100 m/min = 12/40 × 100 = 0.3 × 100 =30 min.
 
        
             
        
        
        
Step-by-step explanation:
4x2 - 25b2 
We can solve it by the squares so
(2x - 5b) (2x + 5b)
2) x2 - 81 
 The same case is here so
 (x - 9) (x + 9)
 
        
             
        
        
        
Answer:
The order of operations is PEMDAS
First step is to do everything is parenthesis or brackets
5+{2*[(5-1)+6]}/4
{2*[(5-1)+6]}
First you would go 5-1=4, because that is the first equation that is in parenthesis by itself. 
{2*[4+6]}
Next you would go 4+6=10, because that is your next smallest bracket
{2*10} 
Last you would go 2*10=20
Your equation now looks like this
5+{20}/4
In PEMDAS your next step is exponents, but we don't have any so we go on to the next one which is multiply/division 
5+5 
You would go 20/4=5
Last step is to add/subtract
5+5=10
Your final answer would be 10
Hope this helps ;)
Step-by-step explanation:
 
        
             
        
        
        
For the last 2 questions, 
1. 9/10
2. 7/12