The LCM of 6 and 15 is 30:)
Answer: Choice C. 
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Explanation:
The domain is the set of all allowed x inputs.
Here we see that x = -3 is the smallest x value possible as it is from the left-most point. The graph goes on forever to the right, so there is no largest x value. Effectively infinity is the largest x value even though infinity is not a number.
We can say the domain is
which can be simplified to
or 
In short: x can be -3 or larger.
1/2 (6x - 10) + 10 = 5x - 13
(6x/2) - (10/2) + 10 = 5x - 13
3x - 5 + 10 = 5x - 13
3x - 5x = -13 + 5 - 10
-2x = -18
x = -18 / -2
x = 9
D.) x = 9
The answer is -7
2x-3(x+4)=-5
Multiply by -3
2x-3x-12=-5
Collect like terms
-x-12=-5
Move constant to the right to change its sign
-x=-5+12
Add
-x=7
Change the signs
x=-7
There are 8 pigs to every 3 sheep
8 pigs +3 sheep is 11 ÷165 is 15
15×8 is 120
15×3 is 45
so there was 45 sheep