Answer:
Step-by-step explanation:
You can split the coins into 3 groups, each of them has 3 coins. Weigh group 1 vs group 2, if one is lighter, that group has the fake coin. If both groups weigh the same, then group 3 has the fake coin.
Continue to split the group that has the fake coin into 3 groups, each group has 1 coin. Now apply the same procedure and we can identify the fake coin.
Total of scale usage is 2
b) if you have 
coins then you can apply the same approach and find the fake coin with just n steps. By splitting up to 3 groups each step, after each step you should be able to narrow down your suspected coin by 3 times.
Step 1: you narrow down to group of 
coins
Step 2: you narrow down to group of 
coins
Step 3: you narrow down to group of 
coins
...
Step n: Step 1: you narrow down to group of 
coin
Answer:
Step-by-step explanation:
Answer:
12,495 is the answer
Step-by-step explanation:
X-4y=13 would match the best
Answer: y - 5 = 0(x - 1)
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Explanation:
Recall that point slope form in general is written as such
y - y1 = m(x - x1)
where,
m is the slope
(x1,y1) is the point the line goes through
The given equation y = 7 can be written as y = 0x+7. So we see that this line has a slope of m = 0
Plug m = 0 along with the given point (x1,y1) = (1,5) into the point slope equation and we get
y - y1 = m(x - x1)
y - 5 = 0(x - 1)
which is the final answer
note: the equation in bold can be rearranged and simplified to get y = 5; however your teacher seems to want the answer in point-slope form, so we leave it as such.
