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How to solve it in quadratic functions

How to solve it in quadratic functions-example-1

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Answer:

x = 2

x = -3/2 or -1.5

Explanation:

For this, I would use the "slip and slide" method. LOL I know the name is cheesy, but that's what my teacher called it!

First, you "slip" the coefficent of the leading term (2) to the constant, and multiply.

The equation becomes:

x² - x - 6(2) = 0

x² - x - 12 = 0

Then, you factor this out by looking at the second and third terms. You're looking for 2 factors of -12 that would add up to -1 ( the coefficent of the second term).

Automatically, think of 3 and 4, because the difference between them is 1.

The factors must be (x-4) and (x+3) because they multiple to -12, and add up to -1.

This step is extremely important! Lol I used to forget it a lot, but make sure you divide the constant in each factor by the original number you "slipped".

It would become (x-(4/2))(x+3/2) = (x-2)(x+3/2)

With (x+3/2), you don't want to leave it as a fraction or decimal. It's equivalent to (2x+3). However, the informal form is easier to identify the value of x.

User Ykesh
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