Answer:

Step-by-step explanation:
To find the LCM of 1,2,12,30,84,165 you must first find the prime factors of 12,30,84 and 165
12| 2 30| 2 84| 2 165| 3
6 | 2 15 | 3 42| 2 55 | 5
3 | 3 5 | 5 21 | 3 11 | 11
1 1 7 | 7 1
1

Now we look for common and uncommon factors with their greatest exponent
LCM(1,2,12,30,84,165)
Common factors with their greatest exponent: 
Uncommon factors with their greatest exponent: 

Answer: x=50
Step-by-step explanation:
18*x-(900)=0
Pull out like factors: 18x-900=18x(x-50)
18=0
x-50=0
Add 50 to both sides of the equation:
x=50
The image of the diagram is missing, so i have attached it.
Answer:
a = 30°
Step-by-step explanation:
From the diagram attached, we can see that the 2 angles a and 5a are interior supplementary angles.
The sum of interior supplementary angles is 180°
Thus;
5a + a = 180
6a = 180
a = 180/6
a = 30°