Answer:
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Step-by-step explanation:
By definition, we can write ln instead of log. WHEN??
Whenever the base of the logarithm is the number "e".
Hence, when we have:
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We can write it in shortcut as:
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Hence, ln x can also be written as 
Fourth answer choice is right.
If we have 2 coordinates say: (x1,y1) and (x2,y2)
Then the formula for the midpoint is:
((x1+x2)/2,(y1+y2)/2)
And the formula for the distance is:
Sqrt((x2-x1)^2+(y2-y1)^2)
So here we have (-1,-4) and (-7,4)
The midpoint is:
((-1+-7)/2,(-4+4)/2) = (-8/2,0/2) = (-4,0)
The distance is:
Sqrt((-7- -1)^2+(4- -4)^2)
= sqrt((-6^2)+(8^2))
=sqrt(36+64)
=sqrt(100)
=10
I just took the test the answer is 9 cm.
So use cancelation
multiply first equation by 2
2x+8y=10
times 2
4x+16y=20
now add
4x+16y=20
<u>-4x-9y=-13 +
</u>0x+7y=7
7y=7
divide by 7
y=1
subsittue
2x+8y=10
2x+8(1)=10
2x+8=10
subtract 8 from both sides
2x=2
divide by 2
x=1
x=1
y=1
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To identify meauserment / user mistakes made when measuring.