# How do you solve #y^2 + 10y + 35 = 0# by completing the square?

##### 2 Answers

#### Explanation:

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#### Explanation:

This is a quadratic in

Set as

Write as:

The

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Take the index (power) outside the brackets

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Discard the

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Halve the 10

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Now we need to correct for the error. The 5 in

So

This is also known as the Vertex Form Equation

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Square root both sides

As soon as you see a root of a negative it means Complex Numbers are involved. In other words; the plot does not cross the y-axis in this case. If the graph was of general shape