Question

Billie solved the equation below by completing the square, but she got the incorrect solution. In which step did Billie first make an error? Choices: 1234
Step 1: x^2+10x=49

Step 2: x^2+10x+25=49

Step 3: (x+5)^2=49

Step 4: x+5=+-7

Step 5: x=2, x=–12

Answer 1

Answer:

step 2

Step-by-step explanation:

we have

$x^{2} +10x-49=0$ ---> given problem

step 1

Move the constant to the right side

$x^{2} +10x=49$

the step 1 is correct

step 2

Complete the square

$x^{2} +10x+5^2=49+5^2$

$x^{2} +10x+5^2=74$

The step 2 is not correct

step 3

Rewrite as perfect squares

$(x+5)^{2}=74$

step 4

take square root both sides

$x+5=\pm\sqrt{74}$

step 5

Find the values of x

$x=-5\pm\sqrt{74}$

$x=-5+\sqrt{74}$

$x=-5-\sqrt{74}$