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What number would you add to both sides of x² + 7x = 4 to complete the square?

O 22
072
O 7²
2
(3²

User Janos
by
2.6k points

2 Answers

19 votes
19 votes

Answer:

Then we need to add (b/2)^2=49/4 to both sides to complete the square.

Add 49/4 to both sides.

x=−7/2 + 1/2√65 or x=−7/2 + -1/2√65

Explanation:

Let's solve your equation step-by-step.

x²+7x=4

Step 1: The coefficient of 7x is 7. Let b=7.

Then we need to add (b/2)^2=49/4 to both sides to complete the square.

Add 49/4 to both sides.

x²+7x+49/4=4+49/4

x²+7x+49/4=65/4

Step 2: Factor left side.

(x+7/2)2=65/4

Step 3: Take square root.

x+7/2=±√65/4

Step 4: Add (-7)/2 to both sides.

x+7/2+−7/2=−7/2±√65/4

x=−7/2±√65/4

x=−7/2 + 1/2√65 or x=−7/2 + -1/2√65

User Jack Tiong
by
2.8k points
22 votes
22 votes

Answer:

Explanation:

That would be (7/2)^2

= 49/4.

User Prola
by
2.7k points
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