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4 - 5/2 * (1/10x) = 1 what is the value of x

User Poppel
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1 Answer

5 votes


4 - 5 / 2 * (1/10x) = 1\\

The first step is to identify the order in which the equation must be solved, by following PEMDAS (you might know it as BEDMAS):

Parenthesis (or Brackets)

Exponents

Multiplication and Division

Addition and Subtraction

My advice would be to add parenthesis, following these rules, if you are not very good at finding them immediately by sight.

So:


4 - 5 / 2 * ((1)/(10x))  = 1\\\\4 - [(5/2)*((1)/(10x))]=1\\\\4-(2.5*(1)/(10x))=1\\\\4-(2.5)/(10x)-1=0\\3-(x)/(4)=0\\(x)/(4)=3\\x=3*4\\x=12

We check our answer:


x=12\\4 - [(5 / 2) * (1/10)*(x)] = 1\\4 - [(5 / 2) * ((1)/(10)) * (12))] = 1\\4 - [2.5 * ((1)/(10))*12] = 1\\4 - [((2.5)/(10))*12] = 1\\4 - [((1)/(4))*12] = 1\\4 - 3 = 1\\1=1

We are right!

So,
x=12.

User Draca
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