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I need help simplifying this expression. (7/2 × -2) - (3/2 × -1) can I also have a step by step explanation that I can write down as notes? I'm struggling.

User Alexhg
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1 Answer

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WE need to complete the following operation of rational numbers:

(7/2) times (-2) and this quantity minus the quantity (3/2) times (-1)

so, as with all operations with numbers we need to perform the Multiplications BEFORE we perform any Addition or Subtraction.

We have two products (multiplications) to perform:

first one: (7/2) times (-2)

with product of fractions, we first multiply their sings (positive times negative will render a negative). Then we multily numerator times numerator, and denominator times denominator separately. In our case: 7 times 2, which gives 14 in the new numerator, and then 2 times 1 (notice no denominator for the second number (-2) is in fact a one), which gives 2.

Then first produc is : (7/2) * (-2) = -14/2 = -7

Now for the second product:

(3/2) times (-1) . We wrok similarly and get:

Sign = positive times negative = negative

3 times 1 = 3

2 times 1 = 2

that gives the fraction: 3/2

Completed product gives: (3/2) times (-1) = -3/2

And finally, we combine these two values with the subtraction (minus symbol) that separated them:

-7 - (-3/2) = - 7 + (3/2)

Notice that subtracting a negative 3/2 is the same as adding 3/2

then we express -7 in fraction form with denominator 2, as -14/2 (so we can perform the combinationof the two numbers)

-14/2 + 3/2 = -11/2

User Kostas
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