<h3>
Answer: (-infinity, 7]</h3>
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Explanation:
The first interval (-infinity, 3) describes any number less than 3, so we can write x < 3 in short hand (where x is the unknown number).
The second interval (-1, 7] means we start at -1 and stop at 7. We do not include -1 but include 7. So we say that 
(ie x is between -1 and 7; exclude -1, include 7)
If you were to graph each ona number line, you would see that the too intervals have overlapping parts. The right most edge extends out as far as x = 7. There is no left most edge as it goes onforever that direction.
Therefore, the to intervals combine to get 
which turns into the interval notation answer of (-infinity, 7]
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It might help to think of it like this: x < 3 and say "x is some number that is less than 3, or it is between -1 and 7". So x could be anything less than 7, including 7 itself.
Answer: k=-6
-6=k+0
Step-by-step explanation:
Answer:
10 didn’t eat chickens
Step-by-step explanation:
30-20=10
The answer of the question is 140. hope i help you ;)
Answer:
f(x)=
1. 48x when x < or = 3,
2. 45x when 4 < or = x < or = 8
3. 42x when 9 < or = x < or = 19
4. 38x when x > 19
Step-by-step explanation:
3 boxes or less = Cost of tiles = $48
4 - 8 boxes ; cost = $45
9 - 19 boxes ; cost = $42
> 19 boxes ; cost = $38
