Suzie solved the equation 9x−5=14(16x+60)

using the following steps:

1) Distribute 1/4 to get 9x−5=4x+60


2) Use subtraction property of equality to move 4x to get 5x−5=60


3) Use addition property of equality to move 5 and get 5x=65


4) Use division property of equality to get x=13


Determine if Suzie solved correctly - if not, identify which step was the mistake.

(1 point)
Responses

Suzie made a mistake on Step 1 - she should have distributed the 1/4 to 60 as well
Suzie made a mistake on Step 1 - she should have distributed the 1/4 to 60 as well

Suzie made a mistake on Step 2 - she should have used the addition property instead
Suzie made a mistake on Step 2 - she should have used the addition property instead

Suzie solved the problem correctly
Suzie solved the problem correctly

Suzie made a mistake on Step 4 - she divided incorrectly
Suzie made a mistake on Step 4 - she divided incorrectly
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1 answer

To determine if Suzie solved the equation correctly, let's analyze the steps she took and check for any errors.

The original equation is: \[ 9x - 5 = 14(16x + 60) \]

  1. Distributing on the right side: \[ 14(16x + 60) = 14 \cdot 16x + 14 \cdot 60 = 224x + 840 \] Thus, the equation becomes: \[ 9x - 5 = 224x + 840 \] Suzie's Step 1 was incorrect because she does not end up with \( 4x + 60 \).

  2. Continuing from the correct form: \[ 9x - 5 = 224x + 840 \]

  3. Using subtraction property of equality: Subtract \( 224x \) from both sides: \[ 9x - 224x - 5 = 840 \] This simplifies to: \[ -215x - 5 = 840 \]

  4. Using addition property of equality: Add \( 5 \) to both sides: \[ -215x = 845 \]

  5. Using division property of equality: Divide both sides by -215: \[ x = -\frac{845}{215} = -\frac{169}{43} \]

Since Suzie's calculation did not follow the correct procedure from the start, she made a mistake in Step 1 where she incorrectly distributed \( \frac{1}{4} \).

Conclusion: The correct response is: Suzie made a mistake on Step 1 - she should have distributed the 14 to both \( 16x \) and \( 60 \) instead.