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Josephine solved a quadratic equation. Her work is shown below.
In which step did Josephine make an error?
5(x + 7)2 = 245
(x + 7) = 49
Step 1
*+7=7
Step 2
x = 0
Step 3
Choose1 answer.

Respuesta :

Space

Answer:

Step 2

General Formulas and Concepts:

Pre-Algebra

  • Equality Properties

Algebra I

  • Solving Quadratic Equations

Step-by-step explanation:

Step 1: Define

Identify

5(x + 7)² = 245

Step 2: Solve for x

  1. [Division Property of Equality] Divide 5 on both sides:                                 (x + 7)² = 49
  2. [Equality Property] Square root both sides:                                                    x + 7 = ±7
  3. [Subtraction Property of Equality] Subtract 7 on both sides:                        x = ±7 - 7
  4. Simplify:                                                                                                             x = 0, -14

Here, we can see that Josephine made an error at step 2, when she square rooted both sides. Remember when you square root both sides of a quadratic, you will have a ± sign and have multiple roots/solutions.

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