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Solve this equation using the "Distributive Property".


\sf 3(x - 2) = 21


User Rkd
by
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2 Answers

7 votes

Answer:

x = 9

Explanation:

Start by dividing both sides by the singular number, 3. We divide by 3 and not 21 because 21 is the result of the equation, not the coefficient.


(3\left(x-2\right))/(3)=(21)/(3)

We got 21 over 3 because you cannot divide 3 times an unknown number subtracted by 2 by 3. This is because we do not know the number. So that's where 21 comes in.

Next, simplify this equation by dividing whole numbers.


(3)/(3) = 1


1\left(x-2\right) = \left(x-2\right)


(21)/(3) = 7\\= x-2 = 7

Lastly, add 2.


x - 2 + 2 = 7 + 2\\2 + 2 = 4\\7 + 2 = 9\\= x - 4 = 9\\x = 9

Why x - 4 is 0: We assume x is always equal to 1, since 4 does not go into 1, the result would be 0. x - 0 = 0. Therefore, the problem became x = 9.

Hope this helps!

User Aspire
by
5.6k points
6 votes
the answer is x = 9
3x - 6 = 21
3x = 27
x = 9
User Masteusz
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5.3k points