Which pair shows equivalent expressions?
A.2(2/5x + 2)=2 2/5x + 1
B.2(2/5x + 2)=4/5x + 4
C.2(2/5x + 4)=4/5x + 2
D.2(2/5x + 4)=2 2/5x + 8
Solution:

Let us distribute 2 inside the parenthesis.
That is, we use distributive property:
a(b+c)=ab+ac

So, 
Answer:Option (b)

Applying distributive property, a(b+c)=ab+ac



So, Option (B) is correct.
Answer:
The correct answer is - an observational study.
Step-by-step explanation:
It is given that, Researchers periodically survey a few thousand of the patients. These are taking specific medicine patients and researchers taking this survey to find the connection between that medication and the subjects' general health.
So, it can say that the researchers observed the patient's health by the effect of the medication, therefore, the Observational Study is the given method of gathering data.
Answer:
7
Step-by-step explanation:
58 divided by 8 is 7
Answer:
x = 20
Length = 20ft
Width = 12ft
Step-by-step explanation:
A = 240
x^2 - 8x = 240
x^2 - 8x - 240 = 0
x^2 - 20x + 12x - 240 = 0
x(x-20) + 12(x-20) = 0
(x+12)(x-20) = 0
x = 20
x = -12 (which we discard since x is a length)
So the dimensions are 20ft and 20-8 = 12ft
The answer is: [D]: "Subtract 5 from 10" .
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Explanation:
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Use the correct order of operations, according to the mnemonic:
"PE MD AS".
The "P" stands for "parentheses", which takes top (first priority); and there are values in parentheses in this expression—specifically, the "(10 - 5)" . So the first step is to "subtract 5 from 10" —which is: "Answer choice: [D]".
Your error was starting at the beginning of the problem; and not using the "order of operations".
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