Let's break down the steps given in the problem and identify where the missing reason might be.
You have the equation:
\[ 2(x + 3) = 10 \]
-
Distributing:
\[ 2x + 6 = 10 \]
(Justification: Distributive property of multiplication over addition) -
Subtracting 6 from both sides:
\[ (2x + 6) - 6 = 10 - 6 \]
(Justification: Subtraction property of equality) -
Simplifying both sides:
\[ 2x + 0 = 4 \]
(Justification: Additive Identity) -
Removing the zero:
\[ 2x = 4 \]
(Justification: Substitution) -
Dividing both sides by 2:
\[ (2x)/2 = 4/2 \]
(Justification: Division property of equality) -
Simplifying:
\[ 1x = 2 \]
(Justification: Division property of equality) -
Final result:
\[ x = 2 \]
(Justification: Substitution)
Now, looking at all of these steps, it appears that the missing justification is step 1, where you distribute the 2. Since the initial step of expanding \(2(x + 3)\) is an application of the Distributive property of multiplication over addition.
Given the options you provided:
- A. Associative property of addition
- B. Commutative property of addition
- C. Multiplicative property of equality
- D. Distributive property of multiplication over addition
The correct answer is D. Distributive property of multiplication over addition as the missing reason.