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.

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

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

1.   an exact solution requires a radical solution - no decimal approximation.2. (a)4x^3 = 756x^3 = 756/4 = 189x =   cube root of 189 =   5.74   to nearest hundredth answer(b)   189 = 3*3*3*7   so we can write the cube root of 189 as 3∛7 answerchecking (a) 4*(5.74^3 =   756.48   which is very close(b)   4* ((3∛3)^3   = 4*189   = 756   - spot on! 3. i would use solution b because the original question asked for an exact solution.