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Ray Of Light [21]

3 years ago

10

Billie solved the equation below by completing the square, but she got the incorrect solution. In which step did Billie first ma

ke 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

1 answer:

Tanzania [10]3 years ago

5 0

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

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

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

<u><em>The step 2 is not correct</em></u>

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

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

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

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

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Answer:

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Step-by-step explanation:

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Use the same rules as applied in the first problem. Also, keep the distributive property in mind. In simple terms, the distributive property states the following ( $a(b+c)=(a)(b)+(a)(c)=ab+ac$ ). Also note, a term raised to an exponent is equal to the term times itself the number of times the exponent indicates. In the event that the term raised to an exponent is a constant, one can simplify it. Apply these properties here,

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