Statement 2(x + 3) = 10 2x + 6 = 10 (2x + 6) - 6 = (10) - 6 (2x + 6) - 6 = 10 - 6 2x + (6 - 6) = 10 - 6 2x + 0 = 10 - 6 2x + 0 = 4 2x = 4 (2x)/2 = 4/2 1x = 2 x = 2 Reason Given Subtraction property of equality a-ba-b Associative property of addition a - a = 0 (Additive Inverse) Substitution a + 0 = a (Additive Identity) Division property of equality Substitution 1a = a (Multiplicative Identity) 自 + < A student solved the given equation and justified every step except one. What is the missing reason? A Associative property of addition B Commutative property of additionMultiplicative property of equalityMultiplicative property of equality

D Distributive property of multiplication over additionDistributive property of multiplication over addition

1 answer

Let's break down the steps given in the problem and identify where the missing reason might be.

You have the equation:
\[ 2(x + 3) = 10 \]

  1. Distributing:
    \[ 2x + 6 = 10 \]
    (Justification: Distributive property of multiplication over addition)

  2. Subtracting 6 from both sides:
    \[ (2x + 6) - 6 = 10 - 6 \]
    (Justification: Subtraction property of equality)

  3. Simplifying both sides:
    \[ 2x + 0 = 4 \]
    (Justification: Additive Identity)

  4. Removing the zero:
    \[ 2x = 4 \]
    (Justification: Substitution)

  5. Dividing both sides by 2:
    \[ (2x)/2 = 4/2 \]
    (Justification: Division property of equality)

  6. Simplifying:
    \[ 1x = 2 \]
    (Justification: Division property of equality)

  7. 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.